Effect Of Temperature Rise Research Articles

BPANN modified constitutive descriptions for flow behavior and softening mechanism in the α+β phase region of Ti-55511 alloy with equiaxed microstructure

The deformation behavior of Ti-55511 alloy was investigated by hot compression tests conducted at deformation temperatures of 993∼1113 K and strain rates of 0.001–1 s−1. To eliminate the effects of friction and adiabatic temperature rise on the flow stresses, the flow curves were corrected. Subsequently, a strain compensated Arrhenius (SCA) model was developed and further modified using the back propagation artificial neural network (BPANN) method. The modified model exhibits significant improvements compared to the SCA model. The average absolute relative error (AARE) decreases from 4.895 % to 0.756 %, while the relative error (δ) range decreases from −14.75 %–17.99 % to −4.78 %–8.01 %. Moreover, cross-validation also confirms the modified model has higher generalization ability and prediction accuracy than the SCA model. Microstructural characterization reveals dynamic recrystallization (DRX) of the α phase and dynamic recovery (DRV) of the β phase are the main mechanisms responsible for softening, and their volume fractions increase with decreasing strain rate and increasing deformation temperature. The equiaxed α phase undergoes elongation first, followed by gradual migration and transformation of grain boundaries. Finally, the β phase wedges into the α phase until the α phase separates. The continuous dynamic recrystallization (CDRX) of β phase accompanies its DRV, which is mainly characterised by progressive sub-grain rotation. The α grains aggregated by dislocations promote CDRX of the β phase.

Research on charging strategy of electric truck considering charging duration, energy loss, and temperature change

The research on charging strategy is a key research direction in the field of electric trucks. This paper establishes an electric-thermal-energy consumption coupling charging model for the power battery of electric trucks. A multi-stage constant current charging (MSCC) strategy based on genetic algorithm is developed. In order to verify the feasibility of the developed MSCC strategy, a comparative study with the traditional constant current charging (CC) strategy was conducted. The simulation results show that under the same charging time (3600 s), compared with the CC strategy, the MSCC strategy reduces the charging energy consumption by 3.78 J and the battery temperature change by 0.69 °C. Furthermore, in order to meet the charging requirements of different scenarios, the MSCC strategy is divided into three charging modes: economic mode, safe mode, and balanced mode. Compared with the CC strategy, the energy loss of the MSCC strategy in the economic mode reduces by 9.55 J, and the economic mode significantly improves the energy saving effect. Compared with the CC strategy, the battery temperature change of the MSCC strategy in the safe mode reduces by 0.82 °C, and the safe mode significantly improves the inhibitory effect of temperature rise during battery charging.

Warm Temperature Increments Strengthen the Crosstalk between Roots and Soil in the Rhizosphere of Soybean Seedlings.

The plant rhizosphere underlies the crosstalk between plant and soil and has a crucial role in plant growth and development under various environments. We examined the effect of temperature rise on the rhizosphere environment of soybean roots to clarify the rhizosphere crosstalk between roots and soil in response to warm temperature rises in a global warming background. The in situ results of root enzyme activity revealed that soybean roots secrete β-glucosidase, and enzyme spectrum imaging demonstrated different enzymatic activities under different temperature environments. The soil enzyme kinetics results showed that soil enzymatic activity increased with increasing temperature, and soybean rhizosphere soil enzymatic activity was higher than that of non-rhizosphere soil. Rhizosphere soil and non-rhizosphere soil showed that the dominant bacterial phylum in soybean rhizosphere soil was Acidobacteria, and the dominant bacterial genus was JG30-KF-AS9. Compared with non-rhizosphere soil, rhizosphere soil was more nutrient-rich, and root secretions provided abundant carbon sources and other nutrients for soil microorganisms in the rhizosphere. Rhizosphere microorganisms affect plant growth by influencing the decomposition of soil organic carbon. The organic carbon content of rhizosphere soil was higher than that of non-rhizosphere soil under high temperatures.

Projected Climate Change Effects on Global Vegetation Growth: A Machine Learning Approach

In this study, a machine learning model was used to investigate the potential consequences of climate change on vegetation growth. The methodology involved analyzing the historical Normalized Difference Vegetation Index (NDVI) data and future climate projections under four Shared Socioeconomic Pathways (SSPs). Data from the Global Inventory Monitoring and Modeling System (GIMMS) dataset for the period 1981–2000 were used to train the machine learning model, while CMIP6 (Coupled Model Intercomparison Project Phase 6) global climate projections from 2021–2100 were employed to predict future NDVI values under different SSPs. The study results revealed that the global mean NDVI is projected to experience a significant increase from the period 1981–2000 to the period 2021–2040. Following this, the mean NDVI slightly increases under SSP126 and SSP245 while decreasing substantially under SSP370 and SSP585. In the near-term span of 2021–2040, the average NDVI value of SSP585 slightly exceeds that of SSP245 and SSP370, suggesting a positive vegetation development in response to a more pronounced temperature increase in the near term. However, if the trajectory of SSP585 persists, the mean NDVI will commence a decline over the subsequent three periods (2041–2060, 2061–2080, and 2080–2100) with a faster speed than that of SSP370. This decline is attributed to the adverse effects of a rapid temperature rise on vegetation. Based on the examination of individual continents, it is projected that the NDVI values in Africa, South America, and Oceania will decline over time, except under the scenario SSP126 during 2081–2100. On the other hand, the NDVI values in North America and Europe are anticipated to increase, with the exception of the scenario SSP585 during 2081–2100. Additionally, Asia is expected to follow an increasing trend, except under the scenario SSP126 during 2081–2100. In the larger scope, our research findings carry substantial implications for biodiversity preservation, greenhouse gas emission reduction, and efficient environmental management. The utilization of machine learning technology holds the potential to accurately predict future changes in vegetation growth and pinpoint areas where intervention is imperative.

Analyses on thermal vibration and stability of sandwich skew plates with functionally graded porous core

In this study, vibration and stability of sandwich skew plates possessing functionally graded porous cores were investigated including significant effect of temperature rise. The modified formulations used for describing the temperature distributions across the plate’s thickness were utilized to carry out the critical buckling temperature and thermos-elastic vibration results. The equations of motion in accordance with the first-order shear deformation theory including the transverse shear effect were solved via the Gram-Schmidt-Ritz method. This method is able to produce accurate solutions of such complex-shaped plates with numerically stable displacement functions generated by Gram-Schmidt procedure for various combinations of boundary conditions. Several important effects such as skew angle, porous coefficient, thickness ratio, aspect ratio, temperature, etc., that have a considerable impact on thermal stability and vibration of such sandwich skew plates are taken into account. According to the numerical experiments, it can be revealed that the critical bucking temperature and frequency of the plates increase considerably with the increase of skew angle. New findings of this study can serve as the benchmarking results for future studies.

Simulation Study of Transient Eddy Current Effect in 3T Animal Gradient Coil

In the process of high-field magnetic resonance imaging (MRI), the eddy current modeling and simulation of the cold screen and metal parts are not highly accurate. To solve this problem, this paper uses the target field method to design a 3T animal gradient coil model. To get more realistic simulation results, a complex model including a gradient system, cryogenic vessel, cold screen, epoxy resin, and temperature holes was constructed. The model was refined using the finite element method, and the effects of eddy currents induced by the gradient coil on the cylindrical cryogenic container and cold screen in the superconducting magnetic resonance instrument under the state of multi-physical field coupling were simulated. The model effectively reflects the transient eddy current distributions on the cold screen and cryogenic vessel in the MRI system and their time-dependent temperature rise effects.

Effect of temperature rise on a tandem of ball-bearings with an O-configuration in motorized spindle under oil-air lubrication

Accurately predicting the thermal behavior of motorized spindles is a critical task in manufacturing industry. In this study, a thermo-mechanical-solid coupling-behavior on the motorized spindle in working condition was investigated and analyzed. Firstly, the bearing mechanical analysis of the motorized spindle under assembly constraints was discussed and a new coupling model was founded. Concurrently, the impacts of oil film thickness and the spacing rings on the displacement were considered into this model. Secondly, for the deformation of bearing, combined with Jones-Harris's quasi-static force–deformation bearing model, a mathematical model about a tandem of ball-bearings was built. And in this model, a new analytical method was proposed to decouple the deformation generated by thermal and centrifugal forces from the Hertz contact deformation, making the deformation analysis clear and orderly. Thirdly, from the perspective of heat generation mechanism and principle, based on the above bearing model, the elastohydrodynamic lubrication analysis on the bearing was executed, the thermal network model of bearing with multiple heat sources was set up, and the bearing node's scheme was optimized. Eventually, the effects of parameters such as speed, cooling water flow, and air flow on temperature rise and bearing parameters were calculated and analyzed, and the theoretical results were examined by tests, which provides some reference and guidance for the structural design of precision spindle.

Effect of Rise in Temperature (250°C) on the Physico-Mechanical Properties of Rubber Mortars

Abstract The recovery and use of waste in the field of civil engineering, particularly in construction materials, is one of the most prominent solutions for preserving the environment. In order to evaluate the results obtained, it is necessary to study the evolution of the properties of these new materials in the different environments where they can live or be exposed, and why not develop an effective method of treatment of such materials for the possibility of their use even in the field of precast concrete. The objective of this work is to study the effect of the increase in temperature as a living environment or as a treatment on the physico-mechanical properties of a crumbled mortar, a potential source of many environmental and economic problems. Hence the screening and the possibility of using these new mortars with sufficient physico-mechanical properties for masonry and why not for prefabrication. The formulation of the mixtures based on the substitution of dune sand by crumb rubber, at different weight contents 10, 20 and 30%. Consequently, prismatic specimens (4x4x16) cm3 subjected to the temperature (250°C), with a speed of 2°C/min followed by a one-hour plateau at the target temperature then cooling to the ambient temperature. The results obtained show that the maximum mass loss is 5% for 30% substitution and that for 10% substitution the absorption by total immersion decreased by more than two thirds and the porosity accessible to water decreased by more than half. The compressive strength increases by 8.9% for 10% substitution and the minimum decrease in tensile strength by bending is at the same substitution of an order of 26.9%. Using the analysis of variance, the influence of the substitution of dune sand by rubber crumbs and of the rise in temperature to 250°C on the behavior of the mortar acquired. Patterns developed by response surface methodology were significant for all p-value substitutions <5%. The results of the numerical optimization showed that the best mixture could obtained by replacing 30% of dune sand with rubber crumb and subjecting the hardened mortar obtained from this mixture to the temperature of 135°C.

Experimental study on charging energy efficiency of lithium-ion battery under different charging stress

Accurate measurement of the energy efficiency of lithium-ion batteries is critical to the development of efficient charging strategies. Energy efficiency is discussed in published work from the perspective of cell design, more than that, the insufficient probe of stresses influencing the energy efficiency of commercialized batteries while the conclusions coupled with the effect of battery temperature rise have limited engineering guidance value. Few papers specify test profiles for energy efficiency baseline. This paper designs a charging energy efficiency (CEE) test profile to present an offline map of baseline value for commercial ternary lithium-ion batteries. The time-frequency domain impedance characteristics are analyzed based on the distribution of relaxation times, providing a mechanistic explanation of the CEE evolution. The contributions of temperature, capacity-rate (C-rate), and state of charge (SOC) to the CEE are quantified by global sensitivity analysis and range statistics. The findings show that the proposed profile decouples the effect of temperature rise under forced convection conditions, and has an error of less than 0.04 % for 3 cycles compared to the FreedomCAR guidance of at least 10 cycles. The CEE-SOC curve shape is similar to “M”, which is attributed to the impedance curve shape of “W”, breaking the previous inherent experience of “lower impedance in the middle SOC”. The median of the Map is 0.964, concomitantly the outlier points are concentrated below 0.887 at 10 °C. The global sensitivity analysis carried out by the Sobol method and the range statistical indicates that the importance ranked is C-rate > Temperature > SOC, with the range statistical of each stress being 11.8 %, 10.223 %, and 7.51 %, respectively, as well as the total-order Sobol indexes being 0.56, 0.439, and 0.066, which is beneficial for optimizing the operating SOC interval of lithium-ion batteries and guiding the development of fast charging strategies.

Life cycle assessment of soil stabilization using cement and waste additives

Environmental measures show that the effect of global temperature rise goes beyond the natural cycle of the Earth’s environmental system, which affects the social, economical, and health conditions of humanity. In this respect, initially, the UN’s sustainable development goals were adopted where, more recently, a UN net-zero coalition was formed to cut greenhouse gas emissions to as close to zero as possible by 2050 to resist foreseen catastrophic outcomes. As a result of these overwhelming goals and regulations, many nations are setting policies to achieve those targets. Nevertheless, such targets, to the best of our knowledge, have not penetrated well into construction applications. In this study, in addition to the mechanical responses of three different waste additives (bottom ash, marble dust and tire rubber powder to replace cement to stabilize problematic soils, a life-cycle assessment was performed to evaluate environmental impacts. Furthermore, a novel impact-performance approach has been introduced to satisfy safety, performance, and sustainability criteria. In this respect, unconfined compressive strength (UCS), initial stiffness (G0), accumulated loss of mass (ALM) due to wet-dry cycles, and life-cycle analysis (LCA) were performed on artificially cemented (7%, 10%, and 13%) clay specimens, compacted at 1600 and 1800 kg/m3 and cured for 28 days. Further, bottom ash (BA) (10% and 20%), marble dust (MD) (20% and 40%), and tire rubber powder (TRP) (2.5%, 5%, 10%, and 20%) were used to replace the cement, which is known for its great environmental impact. It is reported in this study that 2.5% TRP replacement of cement at low density seems to be the optimum dosage and additive, among others, to provide the best performance (UCS, G0, and ALM). Furthermore, the increase in cement content and density results in a positive contribution to performance indicators and a negative contribution to environmental impact. However, when impact-performance is considered, the opposite was observed, i.e., the rise in cement content, additive content, and density results in favourable contributions.

Thermo-elastohydrodynamic lubrication performance study of step seal under transient condition

Purpose This paper aims to study the impact of transient velocity changes on sealing performance during reciprocating sealing processes. Design/methodology/approach Establish a model of transient mixed lubrication, solve the transient Reynolds equation, consider the effect of temperature rise at the seal interfaces, and determine the behavior of the seal interfaces, such as film thickness and fluid pressure. Evaluation with friction and leakage rate, calculate the variation of sealing performance with reciprocating velocity under different working conditions, and verify it through bench experiments. Findings Within a reciprocating stroke, the frictional force decreases with increasing velocity, and the frictional force of the outstroke is greater than that of the instroke; at the time of the stroke transition, the fluid pressure is smallest and the rough peak contact pressure is greatest. At present, the dynamic pressure effect of fluids is the largest, and the friction force also increases, which increases the risk of material wear and failure. Friction and leakage increase with increasing pressure and root mean square roughness. As temperature increases, friction increases and leakage decreases. In studying the performance variations of seal components through a reciprocating sealing experiment, it was found that the friction force decreases with increasing velocity, which is consistent with the calculated results and more similar to the calculated results considering the temperature rise. Originality/value This study provides a reference for the study of transient sealing performance.

Numerical and experimental research on electromagnetic-thermal and leakage defects characteristics of the high voltage cable terminal

Thermal and insulation performance of the High Voltage Cable Terminal (HVCT) could effectively improve the reliability and economy of power energy transmission. In this paper, a numerical model of the electromagnetic heat flow field was proposed to analyze the heat transfer and temperature characteristics of HVCT under oil leakage defects. This model was the first validated using operation data from the actual equipment and the relative error was less than 1.51%. The effects of oil leakage fault on the global and local temperature distribution of the HVCT were then investigated under different load currents. In addition, the local temperature rise effect of different ambient temperatures on the HVCT oil leakage defect was also considered. Finally, combined with reference indicators such as oil level, temperature, and temperature gradient, a qualitative and quantitative evaluation of the oil leakage fault of HVCT was performed. The results showed that the temperature of the core, surface, and their maximum temperature gradient were linearly related to the ambient temperature. However, the temperature of the core at the oil leak exceeded the normal temperature by up to 7.2 °C with 1000A load current, and the temperature gradient change reaches 681.3 °C/m, which indicated that the convection heat dissipation effect of the oil-deficient part was poor, and the heat accumulates near the cable core. Therefore, the numerical model and analytical results presented in this paper provided an important method for online temperature monitoring and fault analysis of HVCTs.

Estimation of least ecological streamflow through long-term habitat evaluation using stream hydrodynamics and water quality factors

ABSTRACT The objectives of this study were to evaluate aquatic habitat suitability considering stream hydraulics as well as water quality and to propose a stream ecological flow rate for Zacco platypus in the Banbyeon Stream of South Korea. Stream water temperature and dissolved oxygen (DO) in addition to streamflow velocity and depth were simulated using the Hydrologic Engineering Center-River Analysis System (HEC-RAS) from 2010 to 2020 and then used to estimate weighted usable area (WUA) as the proxy indicator of stream habitat suitability. The continuous above-threshold (CAT) analysis revealed several anomalous drops in WUA as the combined effect of water temperature rise and streamflow reduction. A WUA/WUAmax ratio of about 24% seems to be a threshold level below which water temperature rises more rapidly as streamflow decreases. This is equivalent to a streamflow rate of 3.6 m3/s and is proposed as the least ecological streamflow to sustain minimal aquatic habitat suitability.

Influence of uncertainty factors on the dynamic characteristics of magnetorheological damper

The magnetorheological damper (MRD) is a kind of energy dissipation device, which converts vibration mechanical energy into self-heat energy during operation. The dynamic performance of MRD is affected by uncertain factors such as temperature and external magnetic field. In this paper, basing on the temperature rise theory and external magnetic field interference theory of MRD, it analyses the influence of temperature effect and external magnetic field on the dynamic performance of MRD. Under sinusoidal excitation, the internal temperature field and magnetic field distribution of MRD are simulated by COMSOL, and it calculates the changes of temperature and magnetic field in MRD by the conditions of input current of 0.4A, 0.8A and 1.2A. The temperature rise and external magnetic field test are carried out. Under the same input current, the temperature rise of the outer wall of the cylinder is measured. The results show that the input current increases, the temperature rise of MRD increases, and the temperature of MRD increases, the output damping force decreases obviously. When the input current is 0.4A, the temperature of MRD rises to 40℃, the maximum output damping force decreases by 11.2%, and the current is 1.2A, the maximum output damping force decreases by 18.6%. When external magnetic field is applied, the output damping force of MRD increases. The magnetic induction intensity of the external magnetic field increases from 10mT to 30mT, when the incoming current is 0.4A, the maximum output damping force increases by 5.9%, and the current is 1.2A, the maximum output damping force increases by 5.1%. Therefore, applying external magnetic field to compensate the decreasing value of output damping force caused by temperature rise effect has a certain effect. The results show that the variation trend of theoretical analysis, simulation calculation and experimental verification is consistent.

Tribological behavior of ultra-high molecular weight polyethylene (UHMWPE) for acetabular replacement under frictional heat based on molecular dynamics

Abstract Hip prostheses generate higher frictional heat than natural joints at the joint head-socket interface during in vivo service, resulting in higher temperatures of the contact surfaces and surrounding synovial fluid, which affects the frictional properties of the prosthetic material. In order to clarify the influence mechanism of frictional heat on the tribological behavior of ultra-high molecular weight polyethylene (UHMWPE) for acetabular replacement, the tribological tests of three contact pairs were carried out under different synovial fluid temperatures in this research. Furthermore, the movement processes of the molecular chain structure of UHMWPE during friction were simulated by Materials Studio (MS), and the mechanism of oxidative degradation was discussed. The results show that the temperature of synovial fluid has a significant effect on the friction and wear resistance of UHMWPE and the lubrication characteristics of synovial fluid. At the same time, the action mechanism of the proteins in the synovial fluid that gradually precipitate with the temperature rise to participate in the friction process is related to the friction pair material and contact mode. The synergistic effect of temperature rise and friction will accelerate the oxidative degradation reaction of UHMWPE and form ketone and alcohol oxides on its surface, thus reducing its wear resistance.

Multi-Physical Analysis and Optimization in Integrated Lithium Niobate Modulator Using Micro-Structured Electrodes

With the increase in the modulation rate of thin-film lithium niobate (LiNbO3, LN) modulators, the multi-physical field coupling effect between microwaves, light, and heat becomes more significant. In this study, we developed a thin-film LN modulator model using undoped pure LN thin film and T-shaped slow-wave electrodes. Furthermore, we utilized this model to simulate the microwave heating and light heating situations of the modulator. The temperature of the LN modulator was analyzed over time and with different signal frequencies. We also studied the influence of temperature rise on microwave and light signals, and we analyzed the change of S parameters and the Phase Shift of the light signal caused by temperature rise. Finally, we improved the thermodynamic characteristics of the modulator by adding a diamond heat dissipation layer. The diamond was obtained through the Chemical Vapor Deposition (CVD) technique and was a polycrystalline diamond. After adding the diamond heat dissipation layer, the temperature rise of the modulator was significantly improved, and the adverse effects of temperature rise on microwave signals were also significantly reduced.

The influence of temperature rise on the friction torque of ball screw during low speed operation

This study used innovative testing methods to investigate the effect of physical temperature rise on low-speed friction torque of double nut ball screws. 72 experiments were conducted using two samples and three protocols. Found the inflection point temperature and inflection point velocity. Below the inflection point temperature, the frictional torque increases with the increase of speed; Above this temperature, the frictional torque first decreases and then increases. Below this inflection point speed, the frictional torque first decreases and then increases; Above the inflection point velocity, the friction torque decreases with increasing temperature. Based on the Strebeck theory, the variation of friction coefficient with temperature was studied; When it is below the inflection point speed, it fluctuates greatly with the increase of temperature, but when it is above the inflection point speed, the fluctuation is small and steadily decreases with the increase of temperature. In addition, based on the theoretical models of Coulomb friction torque and viscous friction torque, the results of this model are in good agreement with the measurement results above the inflection point speed, indicating the correctness of the theory and providing good theoretical guidance for engineering designers.

Simulation Analysis of Stir Tool Wear Considering the Effect of Temperature Rise caused by Material Deformation on Flow Stress

Background: Wearing is a prominent problem in friction stir welding. The material flow stress equation is a key factor that decides the accuracy of the simulation of the wearing process. Objective: We aim to propose a material flow stress equation based on material true stress and true strain curve, which takes proper factors into account and leads to good accuracy in numerical simulation of stir tool wear. Methods: The value of the material temperature rise caused by the material deformation heat and the value of the effect caused by the temperature rise on flow stress was calculated, and the effect value was used to modify the material flow stress and the related curve, and then the modified flow stress equation was obtained. On this basis, the equation was used to simulate the stir tool wear, and the simulation results were compared with those results without considering the effect of temperature rise. Results & Discussion: the wear amount of the stir needle when considering the effect of temperature rise is significantly less than that when the effect of temperature rise is not considered. Conclusion: In the simulation of the wear of the stir tool, it is necessary to adopt the modified flow stress equation considering the effect of temperature rise.

Real-time monitoring of focused ultrasound therapy using intelligence-based thermography: A feasibility study

Focused ultrasound (FUS) therapy has been widely studied for breast cancer treatment due to its potential as a fully non-invasive method to improve cosmetic and oncologic results. However, real-time imaging and monitoring of the therapeutic ultrasound delivered to the target area remain challenges for precision breast cancer therapy. The main objective of this study is to propose and evaluate a novel intelligence-based thermography (IT) method that can monitor and control FUS treatment using thermal imaging with the fusion of artificial intelligence (AI) and advanced heat transfer modeling. In the proposed method, a thermal camera is integrated into FUS system for thermal imaging of the breast surface, and an AI model is employed for the inverse analysis of the surface thermal monitoring, thereby estimating the features of the focal region. This paper presents experimental and computational studies conducted to assess the feasibility and efficiency of IT-guided FUS (ITgFUS). Tissue phantoms, designed to mimic the properties of breast tissue, were used in the experiments to investigate detectability and the impact of temperature rise at the focal region on the tissue surface. Additionally, an AI computational analysis employing an artificial neural network (ANN) and FUS simulation was carried out to provide a quantitative estimation of the temperature rise at the focal region. This estimation was based on the observed temperature profile on the breast model's surface. The results proved that the effects of temperature rise at the focused area could be detected by the thermal images acquired with thermography. Moreover, it was demonstrated that the AI analysis of the surface temperature measurement could result in near real-time monitoring of FUS by quantitative estimation of the temporal and spatial temperature rise profiles at the focal region.

Effects of anode material on the evolution of anode plasma and characteristics of intense electron beam diode

In this paper, three kinds of materials including graphite, titanium (Ti) and molybdenum (Mo) are used as anodes to figure out the influence factors of anode material on the characteristics of the intense electron beam diode. The results show that the characteristics of diode are mainly determined by the cathode plasma motion under a 15 mm diode gap, in which the typical electron beam parameters are 280 kV, 3.5 kA. When the diode gap is reduced to 5 mm, the voltage of the electron beam reduces to about 200 kV, and its current increases to more than 8.2 kA. It is calculated that the surface temperatures of Ti and Mo anodes are higher than their melting points. The diode plasma luminescence images show that Ti and Mo anodes produce plasmas soon after the bombardment of electron beams. Ti and Mo lines are respectively found in the plasma composition of Ti and Mo anode diodes. Surface melting traces are also observed on Ti and Mo anodes by comparing the micromorphologies before and after bombardment of the electron beam. These results suggest that the time of anode plasma generation is closely related to the anode material. Compared with graphite, metal Ti and Mo anodes are more likely to produce large amounts of plasma due to their more significant temperature rise effect. According to the moment that anode plasma begins to generate, the average expansion velocities of cathode and anode plasma are estimated by fitting the improved space-charge limited flow model. This reveals that generation and motion of the anode plasma significantly affect the characteristics of intense electron beam diode.