Reasonable Process Parameters Research Articles

The Effect of Process Parameter on the Second Phase Particles in Al-Ti-B Master Alloys

Al-Ti-B master alloy is an efficient and practical aluminum grain refiner. This paper studies the effect of process parameter on the Second Phase Particles distributions and shape in Al-Ti-B Master Alloys by casting of pure titanium particale method. Emphatically studied three factors of feeding order, superheating temperature and reaction time , then the reasonable process parameters are put forward.

Investigation on Localisation and Three-dimensional Micro-etching Based on Pulse Laser Electrochemical Machining

By integrating indium tin oxide(ITO) conductive glass into the laser electrochemical micro machining system as tool cathode, the efficient combination of laser electrochemical machining is achieved with laser irradiation. In the established experimental system, the aluminum alloy is etched by the compound processing of laser and electrochemistry. The thermal-mechanical shock effect of laser local irradiation could remove the passivation layer in a uniform electric field, and the material at this zone is etched. However, the other regional material could not be removed because of the protection of the passivation layer, which enhances the localisation of electrochemical machining significantly. The influence mechanism of the thermal-mechanical shock of laser and the refraction characteristic of bubbles on the localization of combined machining is investigated theoretically. Based on the experiment result, the influence of the laser power, machining current and different processing methods on the localization of combined machining is also analyzed. The stray-current corrosion is restrained effectively and a three dimensional cavity with good shape precision and surface quality is acquired successfully with reasonable processing parameters.

Hot workfability behavior of as-cast Mg–Zn–Y–Zr alloy

Hot workability of conventional magnesium alloys, such as AZ61, AZ80 and ZK60, have been proposed or reported in previous literature. However, no detailed investigation has been conducted regarding the hot workability of as-cast Mg–Zn–Y–Zr alloy. The hot deformation characteristics of as-cast Mg–Zn–Y–Zr alloy were investigated using constitutive equations and processing maps at temperatures between 200 and 400°C and strain rates ranging from 0.001 to 1s−1. Backward extrusion of the component with multi-hole was carried out to evaluate the workability of Mg–Zn–Y–Zr alloy at elevated temperatures. The results show that the flow stress has been found to be strongly dependent on temperature as well as strain rate. By means of regression analysis for the Arrhenius type equation of flow behavior, the apparent average activation energy of deformation was determined as 251.228KJ/mol, and the stress exponent was 6.231. The processing map technique was utilized to determine the practical processing parameters. The reasonable process parameters of as-cast Mg–Zn–Y–Zr alloy were deformation temperatures of 350–400°C and stain rates of 0.001–0.1s−1. The reproduction of Mg–Zn–Y–Zr alloy components with multi-hole was shown to be good, and no problem was experienced in filling during backward extrusion using reasonable process parameters.

Boring-Rolling Process Research and Tooling Design of Hydraulic Cylinder

By comparison, this paper determines inner bore processing technic program of the engineering machinery hydraulic cylinder block and makes some analysis of the rolling processing technic and relevant emerging issues to propose reasonable and feasible process route and process parameters and ensure the quality of the cylinder processing. It also shows the design of boring-rolling compound tools with high efficiency and high precision for given cylinders.

Prediction and control of equiaxed α in near-β forging of TA15 Ti-alloy based on BP neural network: For purpose of tri-modal microstructure

For TA15 Ti-alloy in near-β forging and subsequent heat treatment, the evolution of equiaxed α is complex and difficult to control, but a tri-modal microstructure has strict requirements of the volume fraction, size and so on for equiaxed α. In this paper, a prediction model based on improved BP neural network was adopted to investigate quantitative evolution laws of the volume fraction, average grain size, and average aspect ratio of equiaxed α under different deformation temperatures, degrees and strain rates in near-β forging and subsequent high and low temperature double heat treatments (HLT, 950°C/100min/WQ+800°C/8h/AC). Then, taking the tri-modal microstructure as target, the control of equiaxed α was realized and a reasonable processing parameters match of near-β forging under HLT treatment was determined. Finally the reliability of prediction model and results were verified through experiments, and the tri-modal microstructure with excellent mechanical properties was obtained. The results provide a guide for obtaining a tri-modal microstructure of Ti-alloy through the near-β forging technology.

Research on Grain Impacting Load in Abrasive Flow Machining

In order to grasp the microcosmic mechanism of abrasive flow machining (AFM), find out the real law of grain cutting workpiece surface, make out a reasonable process parameters and improve the abrasive flow processing efficiency. The process of grain (near to workpiece surface, called as active grains) cutting workpieces material has been analyzed and the cutting force model has been established in present work. Firstly, at the beginning of the present work, the general process of grain cutting, wearing or deburring workpiece surface has been researched. Theoretical analysis shows that the cutting force not only derives from static force, such as abrasive medium viscoelasticity and grain squeezing, but also dynamic force, such as grain impacting load on the workpiece surface. In ordering to prove the dynamic force exists, one or two main dynamic process parameters (such as abrasive viscosity, extrusion pressure, piston velocity) are chosen, dynamic force is most sensitive to the variation of which, meantime, static force is not, and then the effects of main dynamic process parameters on cutting force value have been compared with the effects of others process parameters by several experiments in the present work. The experimental results show that with the same proportion of variation of process parameters, the change in cutting force (mainly axial cutting force) consists with theoretical results very well in some degree.

Multi-Factors Interaction Effects of Process Parameters on the Joint Strength of Laser Transmission Joining between PC and PA66

This paper presents a laser transmission joining (LTJ) experiment between thermoplastic Polycarbonate (PC) and glass reinforced nylon (PA66GF) using diode laser equipment. Laser transmission joining experimental design and experiment are carried out according to a single process parameters window. Response surface methodology (RSM) in Design-Expert v7 software is employed to develop mathematical models between LTJ process parameters and joint strength. The interaction effects of joining process parameters (line energy, spot diameter, clamp pressure) on the joint strength are investigated using analysis-of-variance (ANOVA), the result shows that the interaction effect of line energy and spot diameter has maximum influence on the joint quality. Finally, the predicted values from mathematical models developed by RSM are compared with the experimental values and it is found that they are nearly agreed with each other. The purpose of predicting joint strength based on reasonable process parameters is achieved.

Research on the 45Mn Materials Forging Properties

In this paper, we study the 45Mn steel material forging performance, and the results show that: as long as choosing reasonable forging process parameters, such as the crack forging defects can be avoided. Through the forging of 45Mn material internal organizational performance in microscopic analysis, found that the microstructure and beginning the determination of forging closely related temperature range, so as to determine the 45Mn steel forging process, for 45Mn steel forging production provides the practical feasible forging process. Keywords: 45Mn, Forging performance, Microstructure, Microscopic analysis, Forging process

Research on Process Parameters Influencing on Cutting Force in Abrasive Flow Machining (AFM)

In order to reduce the cost, improve the surface of workpiece machined by AFM and make out reasonable technological parameters of AFM, AFM theory model has been developed in the present work. The process parameters such as pressure, piston velocity, temperature and viscosity impacting on the workpiece surface quality have been researched. Firstly, the properties parameters of abrasive media such as viscous have been figured out with formulas based on the characters of abrasive media. And then the force between abrasive near to the workpiece surface and workpiece has been modeled with fluidics equations and dynamics equations. However, different parameter value leads to different force and different force has different surface quality (Ra) of workpiece. The calculation result is similar to the experiment result to some extent. Obviously, this model is helpful to establish the reasonable process parameters.

An Experimental Research on Quality and Strength of Aluminous Joint by Clinch Joining Technique

Due to its advantages over the spot welding technique, clinch joining technique is applied extensively in the automobile, electrical apparatus, etc. The quality and strength of the joints are the hot issues of the technique, which are severely affected by the processing parameters and die structure parameters. Clinch joining experiments of aluminous sheetsL5 were carried out under various blank holder forces and die structure parameters, and the influence of the parameters on the failure mode, section quality and strength of the joints were analyzed. The results show that the failure of the joints is mainly the shearing and a good section quality and high shearing strength of the joints can be obtained by reasonable processing parameters and die structure parameters.

Numerical simulation of temperature field in horizontal core-filling continuous casting for copper cladding aluminum rods

The steady-state temperature field of horizontal core-filling continuous casting (HCFC) for producing copper cladding aluminum rods was simulated by finite element method to investigate the effects of key processing parameters on the positions of solid-liquid interfaces (SLIs) of copper and aluminum. It is found that mandrel tube length and mean withdrawing speed have significant effects on the SLI positions of both copper and aluminum. Aluminum casting temperature (TAl) (1003-1123 K) and secondary cooling water flux (600-900 L·h −1 ) have little effect on the SLI of copper but cause the SLI of aluminum to move 2-4 mm. When TAl is in a range of 1043-1123 K, the liquid aluminum can fill continuously into the pre-solidified copper tube. Based on the numerical simulation, reasonable processing parameters were determined.

Finite Element Analysis on Residual Stress of Laser Brazing Diamond Wheel

The purpose of this paper is to simulate the residual field of laser brazing by FEM of ANSYS. The 2-D coupled field element is elected to create finite element model. The brazing experiments have been done by means of 45steel which is the matrix and Ni-Cr solder and the residual stress of the diamond wheel has been measured by Raman method. The results of measure show that the maximum stress value is less strength of diamond. The residual stress distribution is basically identical between the results of simulation and experiment. According to this paper, it is possible to decrease the costs of study by selecting reasonable processing parameters on laser brazing.

Warm/cold rolling processes for producing Fe-6.5wt% Si electrical steel with columnar grains

A new technical prototype for producing Fe-6.5wt% Si electrical steel sheets by directional solidification, heat treatment before rolling, warm rolling, and cold rolling was proposed in the present study. The formability of Fe-6.5wt% Si electrical steel before rolling and the reasonable process parameters of this technical prototype were obtained. Experimental results reveal that the formability of Fe-6.5wt% Si electrical steel is improved significantly under the combination of directional solidification and heat treatment before rolling. Fe-6.5wt% Si electrical steel sheets with the thickness of 0.15 mm, bright surface, few edge cracks, and high rolling yield can be successfully fabricated using this technology without any intermediate annealing during the whole rolling. The combination of directional solidification, heat treatment before rolling, warm rolling, and cold rolling can work as a new process for highly efficient and compact fabrication of Fe-6.5wt% Si electrical steel sheets.

Numerical and experimental study on effect of process parameters on preparation of A356 aluminum alloy semi-solid slurry by electromagnetic stirring

A two-dimensional model coupling of the electromagnetic field, the temperature fieldand theflow fieldof preparation of A356 aluminum alloy semi-solid slurry by electromagnetic stirring (EMS) was established. The Power Law Cut-Off (PLCO) model was used to model the semi-solid slurry. The effect of process parameters such as stirring frequency, stirring current, pouring temperature and crucible preheated temperature on the electromagnetic field, temperature field and flow field were investigated by finite element code ANSYS combined with secondary development INTEL FORTRAN software and corre- sponding experimental verification. The results show that the electromagnetic field and flow field increase as stirring frequency and stirring current increase. Similarly, temperature field and flow field increase as pouring temperature and crucible preheated temperature increase. However, too high stirring frequency, stirring current, pouring temperature and crucible temperature may lead to rapid increase in the flow field, as a result, strongly turbulent flow might occur. The reasonable process parameters for preparation of A356 alloy semi-solid slurry by EMS were obtained. The simulation results are significantly approved with corresponding experimental ones, that verifying the reliability of the calculation models and the software algorithm.

Simulation of dynamic temperature field during selective laser sintering of ceramic powder

It is difficult to obtain the dynamic temperature field and the variation pattern with the experimental method as the temperature field changes very fast in the laser sintering process. In this study, a mathematical model for the dynamic temperature field was established during selective laser sintering (SLS) with nano-hydroxyapatite (HAP) ceramic powder. The dynamic loading of a moving laser heat source with a Gaussian distribution was realized with ANSYS Parameter Design Language. The variation pattern of a three-dimensional transient temperature field at different speeds of the moving laser heat source was analysed as the change of thermal physical parameters with temperature was taken into account in the developed model. The results show that the maximum temperature point on the sintered layer surface is slightly lagged from the laser spot centre with the moving laser heat source when the offset distance is 0.4 mm, laser power is 10 W, laser spot diameter is 2 mm and laser speed is 200 mm/min. The temperature decreases rapidly with the increase of sintering depth. The temperature field that the characteristic microstructure of the sintered parts represents coincides with that by the analysis with finite element calculation. This study may provide useful guidance for selecting the reasonable processing parameters during SLS.

Analysis of stress-etching quality based on nanosecond pulse laser electrochemical machining

Nanosecond pulse laser electrochemical etching can remove the electrolytic products of laser irradiated region and so improve the processing stability and processing efficiency. The stress-etching characteristics and the material removal mechanism for aluminum alloy workpiece were investigated theoretically and experimentally by the use of a laser electrochemical machining system. For comparison of processing topography between laser direct etching in air and laser electrochemical machining, the scanning electron microscopy and the optical profilometry were used to detect and analyze etching morphological characteristics of machining areas. Based on the principle of mechanics and electrochemistry, stress-etching principles of laser electrochemical machining were studied. In this study, the effects of processing parameters and machining method on machining quality were explored, and a complex microstructure was processed successfully with reasonable processing parameters. The results show that laser electrochemical machining with better stability can reduce surface roughness and improve machining quality effectively.

Research of Casting Process about Cover and Pump Body of Tonghai Pump and Mechanical Properties Test

In order to obtain cover and pump body of tin bronze Tonghai pump that is dense and good pressure resistance,the casting mold of the cover of Tonghai pump is metal mold. The casting method of Tonghai pump is vacuum counter-pressure casting.The method of casting pump body of Tonghai pump is vacuum investment casting. This research is about reasonable casting process parameters of vacuum counter-pressure casting and vacuum investment casting.Finally qualified castings of cover and pump body of Tonghai pump can be obtained.

Research on NC Electrochemical Mechanical Drilling

NC electrochemical mechanical drilling was based on NC, Electrochemical machining and mechanical grinding. It drilled with different diameter composite cathodes. This kind of drilling method took the advantages of electrochemical mechanical, so it was not restricted by parts’ strength, hardness and stiffness. The cover of cathode ensured the drilling precision. So this technology should be studied. This paper took 304 stainless steel and high temperature alloy GH710 to do study, at last the reasonable and high efficient process parameters were found in the experiment. The high quality holes of better roundness and small taper angle were drilled. The results showed that the study of NC electrochemical mechanical drilling difficult-to-machine materials was very meaningful.

Welded double sheet hydroforming of complex hollow component

A ‘bone-like’ hollow component with curved axis and complicated cross-sectional geometry was used as the object. The experimental setup for the hollow component by welded double sheet hydroforming was designed and used for the forming of the part. The formability influenced by blank shape and size, loading path combined by the clamping force and liquid pressure was explored, then the reasonable process parameters avoiding defects were obtained. The results show that the reasonable blank shape can not only save materials and reduce costs but also avoid fracture at the corner caused by the large expansion rate and wrinkle in the transition zone of different cross sections. The loading path has a serious effect on the material flow in the pre-forming stage. The complex hollow shell structure with curved axis and varied cross sections can be fabricated by double sheet hydroforming process more easily and efficiently than traditional stamping and welding method. The process can also solve the problem of the limitation of expansion rate by tube hydroforming for the structure with a large difference of cross sections.

Numerical Simulation on the Influence of Heated Mold Continuous Casting Process Parameters to Solid-Liquid Interface

The effect of the position and shape of solid-liquid interface on process parameters has been studied by the numerical simulation method, and the reasonable process parameters have been given. The results shows that the position and shape of solid-liquid interface is mainly affected by mold temperature, casting speed and cooling distance. It were moved to the mold export with the improvement of the mold temperature, casting speed or the reduce of cooling capacity. And the reasonable process parameters are that the mold temperature is 1363-1373 K, casting speed is 80-100mm/min, cooling distance is 40-50mm. The research results would obtain stable operation conditions and improve the billet quality.