Cryogenic Coolant Research Articles

Machining-Induced Damage and Corrosion Behavior of Monel-400 Alloy Under Cryogenic Cooling Conditions: A Sustainable Initiative

AbstractMonel-400 is a nickel-based heat-resistant superalloy (HRSA) that is primarily used in oil and marine applications. Machining Monel-400 alloy for marine applications usually involves drilling and milling operations for assembly purposes, which should meet the requirements to withstand use in salt-water environments (i.e. lower surface finish to reduce corrosion and lack of burrs for tight sealing between mating parts). However, drilling of Monel-400 alloy can be challenging due to its high strength and density, which induces thermal effects that can influence the surface and geometrical integrity of the holes. Consequently, the use of environmentally friendly cooling technologies, such as cryogenics, is an excellent alternative to mitigate these effects, something which has not been widely investigated in the open literature when drilling Monel-400 alloy. Therefore, the current study aims to investigate the machinability of Monel-400 alloy under dry and cryogenic cooling conditions. The effects of cutting parameters and the use of a cryogenic liquid nitrogen bath on the surface integrity and corrosion resistance of holes were evaluated. Additionally, cutting forces, chip formation, and corrosion performance were analyzed. The results showed that the cutting forces increased by up to 8% under cryogenic cooling. Under cryogenic conditions, reduced elastic deformation resulted in a smaller chip size. Both cutting conditions produced a smooth surface finish with a roughness value of less than 0.2 µm. Corrosion resistance was reduced under cryogenic conditions at spindle speed of 5000 rpm. The current work showcases that cryogenic cooling is recommended for drilling Monel-400 alloy used in marine applications, but care should be taken in employing optimal cutting parameters to mitigate any effects on corrosion resistance.

Studies on surface roughness and axial thrust force of drilled holes in Mg-Zn-Ca bio-medical alloy

Mg-Zn-Ca alloy is a promising candidate for orthopaedic implants such as bone plates and screws, as it has a similar mechanical strength and elastic modulus to bone, and it degrades in the body without causing toxicity or inflammation. Drilling studies are necessary to optimize the drilling process parameters, to evaluate the machinability and surface integrity of Mg-Zn-Ca alloy, and to ensure the effective and efficient drilling for various applications in the medical and engineering fields. The present experimental study emphasizes the influence of Ca content, biofriendly coolants and their combined effect with standard drill bits on the surface quality and axial thrust force in the drilling operation of Mg-Zn-Ca alloy. The drilling parameters such as cutting speed, feed rate, standard tools, bio-compatible coolants were optimized with respect to the amount of Ca in the Mg-Zn alloy. The axial thrust force and average surface roughness of drilled holes were considered as response of the experiments. The drilled surfaces were measured for average surface roughness in the transverse direction along the centre path of the drilled hole and a qualitative analysis was also carried out using advanced confocal microscope. The results revealed that the cutting speed among continuous factors significantly influenced the axial thrust force and average surface roughness. The effect of categorical factors was assessed using a regression based ranking method. The results of statistical analysis revealed that high speed steel, and vegetable oil offered improved surface quality, whereas the coconut oil showed low axial thrust force. The liquid nitrogen showed high value of axial thrust force and average surface roughness due to the brittleness induced by cryogenic coolant before drilling operation.

Optimizing Power Consumption in Machining Nickel-Based Superalloys: Strategies for Energy Efficiency

<div>In the face of the world’s population growth and ensuing demands, the industrial sector assumes a crucial role in the management of limited energy supplies. Superalloys based on nickel, which are well-known for their remarkable mechanical qualities and resilience to corrosion, are now essential in vital applications like rocket engines, gas turbines, and aviation. However, these metals’ toughness presents a number of difficulties during machining operations, especially with regard to power consumption. This abstract explores the variables that affect power consumption during the machining of superalloys based on nickel in great detail and suggests ways to improve energy efficiency in this area. The effects of important variables on power consumption are extensively investigated, including cutting speed, feed rate, depth of cut, tool geometry, and cooling/lubrication techniques. A careful balance between these factors is necessary to maximize machining efficiency and reduce power usage. Furthermore, this study reviews the effect of different heat source applications on power consumption and the resultant quality of machined nickel-based superalloys. Additionally, the critical role of cooling and lubrication in mitigating the adverse effects of high temperatures generated during machining is thoroughly examined. Innovative cooling strategies, including cryogenic or high-pressure coolant systems, are explored as potential avenues to enhance heat dissipation and minimize power requirements. In essence, this abstract not only sheds light on the challenges inherent in machining nickel-based superalloys but also offers actionable insights into how energy efficiency can be maximized through strategic parameter optimization and the adoption of innovative cooling techniques. By addressing these aspects, manufacturers can effectively navigate the complexities of machining superalloys while minimizing their environmental footprint and operational costs.</div>

Magnetic properties and cryogenic magnetocaloric effects of rare earth fluorides NH4RE3F10 (RE = Tb, Dy, Ho, Er)

The magnetic properties and magnetocaloric effects of rare earth fluorides NH4RE3F10 (RE = Tb, Dy, Ho and Er) were investigated firstly in NH4-RE-F system. The χ(T) curves show that the materials exhibit a paramagnetic-like behavior and high thermal reversibility. The Curie-Weiss fitting gives that there is an antiferromagnetic interaction between the magnetic moments of RE ions in these materials. Based on the magnetic isotherms data, the values of -ΔSm(T) in the cases of ΔH =10, 20 and 50 kOe were calculated. In the case of ΔH =10 kOe, the -ΔSm(T) of NH4Er3F10 is the largest and the maximum value is about twice as large as that of Gd3Ga5O12(GGG). It indicates that the NH4Er3F10 materials may be candidates of low-field-driven cryogenic magnetic coolant.

Tribological characterization of the cooling performance when applying cryogenic coolants and minimum quantity lubrication

Cryogenic minimum quantity lubrication (MQL) offers the potential to combine high cooling capacities, advantageous lubrication effects and a significant reduction regarding resource consumption. However, due to the wide range of machining applications and different load cases, an efficient design of the respective supply strategy is comparatively difficult. In this study, a tribological approach is presented that enables a characterization of the cooling and lubrication properties in dependence of the supply strategy and two representative load cases. The results show that the tribological setup is well suited to evaluate the occurring thermomechanical loads in dependence of the cryogenic MQL strategies applied.

Effect of Cryogenic Cooling on Micro-milling Properties of Titanium Alloy

Effect of Cryogenic Cooling on Micro-milling Properties of Titanium Alloy

Modeling of Grain Size Change and Phase Transformation of Stainless Wire during Drawing with Cryogenic Cooling

Modeling of Grain Size Change and Phase Transformation of Stainless Wire during Drawing with Cryogenic Cooling

Tuned Windings: the window of opportunity for the implementation of solid conductors in high frequency cryogenic electric machines

Optimization techniques can significantly improve the performance of electrical machines. The analysis and the optimization algorithms focus on computational efficiency. In this paper, the optimization of a high frequency electrical machine in cryogenic conditions is proposed. The losses introduced by AC current in a conductor are directly proportional with the applied frequency in terms of skin effect and proximity effect. The stator coil, made from two aluminium (Al) turns, in the presence of cryogenic coolants has been analysed at frequencies up to 1000 Hz. In order to reduce the AC losses introduced by the magnetic fields, Nonlinear Conjugate Gradient (NCG) method has been applied for the stator coil thickness optimization. Frequency dependence is observed in most simulations. In the presence of Liquid Hydrogen (LH2) coolant, Al 1100 conductor presents the minimum power loss.

A State of the Art on Cryogenic Cooling and Its Applications in the Machining of Difficult-to-Machine Alloys.

Cryogenic cooling has gathered significant attention in the manufacturing industry. There are inherent difficulties in machining materials that are difficult to machine because of high levels of hardness, abrasiveness, and heat conductivity. Increased tool wear, diminished surface finish, and reduced machining efficiency are the results of these problems, and traditional cooling solutions are insufficient to resolve them. The application of cryogenic cooling involves the use of extremely low temperatures, typically achieved by employing liquid nitrogen or other cryogenic fluids. This study reviews the current state of cryogenic cooling technology and its use in machining difficult-to-machine materials. In addition, this review encompasses a thorough examination of cryogenic cooling techniques, including their principles, mechanisms, and effects on machining performance. The recent literature was used to discuss difficult-to-machine materials and their machining properties. The role of cryogenic cooling in machining difficult materials was then discussed. Finally, the latest technologies and methods involved in cryogenic cooling condition were discussed in detail. The outcome demonstrated that the exploration of cryogenic cooling methods has gained prominence in the manufacturing industry due to their potential to address challenges associated with the machining of exotic alloys.

A review of the use of cryogenic coolant during machining titanium alloys

Titanium alloys are considered difficult-to-machine materials, and much effort has been made to improve their machinability through various approaches. The use of cryogenic coolants during machining, sometimes referred to as cryogenic machining, is a popular environmentally friendly technique that promises to reduce cutting zone temperatures, reduce friction, and enhance tool life during machining operations. This review article explores the use of cryogenic coolants during titanium machining and presents an overview of research progress and knowledge gaps. The various coolants and methods for cryogenic machining are reviewed, along with the effectiveness of these methods in terms of key machinability criteria, including tool wear, tribological properties, and heat transfer. Issues in sustainability are also explored.

Cryogenic Cooling in Electronics: The Current State and Future Prospects

Cryogenic Cooling in Electronics: The Current State and Future Prospects

Martensitic Transformation Behavior of Fe–Ni–C Alloys Monitored by <i>In-situ</i> Neutron Diffraction during Cryogenic Cooling

Martensitic Transformation Behavior of Fe–Ni–C Alloys Monitored by <i>In-situ</i> Neutron Diffraction during Cryogenic Cooling

Structural, Electronic, and Magnetic Properties and Magnetocaloric Effect of NdPd Intermetallic Compound for Cryogenic Cooling Applications

Structural, Electronic, and Magnetic Properties and Magnetocaloric Effect of NdPd Intermetallic Compound for Cryogenic Cooling Applications

Exploring the Effects of Ambient Conditions on the Cryogenic Cooling Times of Offshore Structures: Towards Optimising Sustainability and the Decommissioning Timescale

Exploring the Effects of Ambient Conditions on the Cryogenic Cooling Times of Offshore Structures: Towards Optimising Sustainability and the Decommissioning Timescale

Assessment of Environmental Impact by Entropy-Based Approach for Cryogenic Cooling Processes

Assessment of Environmental Impact by Entropy-Based Approach for Cryogenic Cooling Processes

Tribological Analysis of Several Coatings under Flood and Cryogenic Cooling Conditions

The contact between the tool and the workpiece/chip in metal cutting is complex, resulting in high local temperatures and stresses, which may cause severe tool wear and failure. Developments in cryogenic-assisted machining have shown an ecological alternative to the classical metal working fluids, besides tool wear reduction during machining difficult-to-cut materials due to the good ability to dissipate the heat generated by this process. The objective of this work is to analyze the tribological conditions and performance of new coatings specially developed for cryogenic-assisted machining in terms of friction coefficient, volume of build-up material (adhesion) to the tool, and tool temperature. The results have shown that the sliding speed and cooling/lubrication strategy are two main factors that affect the friction coefficient and adhesion of Ti–6Al–4V alloy to the pins. These tribological tests should allow us to select the best coating(s) to be used in cutting tools for further tool wear analysis. Moreover, the obtained friction coefficients could be further implemented into metal cutting models to predict the machining outcomes, including the surface integrity of the machined parts and tool wear.

Experimental Studies of an Induction Motor with Cryogenic Cooling

Experimental Studies of an Induction Motor with Cryogenic Cooling

Side-milling of Incoloy 825 under pulsed and continuous modes of cryogenic cooling

Heat accumulated around the cutting edge significantly impacts the machining process. It results in microcracks development, tool wear enhancement, and work surface quality deterioration. These issues can be somewhat counteracted by applying a cutting fluid at the cutting zones through flood cooling. Cutting fluid waste, however, can be significant and negatively influence the environment. To enhance the effectiveness, a throttle cryogenic coolant (carbon dioxide) is innovatively applied in a pulsed mode on the cutting zone in the milling of Incoloy 825. The pulsed mode of application is realized by periodically opening and closing the supply of the coolant for a given period. The efficacy of the novel system is compared with the conventional approach of applying the cryogenic coolant in the form of a continuous stream. Additionally, the effects of the cutting fluid are also investigated after parallelly adding the stream of micro-lubrication to both modes of the coolant's supply. The effects are investigated on the performance measures of tool wear, cutting forces, and milled surface roughness at the two levels of cutting speed. The experimental results indicated that of the five lubri-cooling techniques tested, the pulsed mode combined with micro-lubrication yielded the lowest cutting forces and the best surface quality. On the other hand, the continuous mode (without micro-lubrication) yielded the best results regarding tool damage. The analyses have also revealed that the parallel application of micro-lubrication in addition to the cryogenic coolant has caused favorable effects on all the performance measures when the coolant is applied in the pulsed mode. Furthermore, the favorable effect is generally more prominent at the low level of cutting speed. In a nutshell, proof of concept is provided in favor of an innovative mode of applying a cryogenic coolant in the form of pulses combined with micro-lubrication for enhancing the viability of milling a nickel-based superalloy.

Machinability analysis for drilling Ti6Al4V ELI under sustainable techniques: EMQL vs LCO2

As a result of the widespread use of Ti6Al4V ELI in the medical industry for implants that are subjected to high loads, these biomedical implants must be accurately machined to prevent unfavourable joint or muscular inflammatory conditions. This oftentimes involve drilling holes into the implants for joint assembly during surgery. It is well known that titanium is a very difficult to machine material and therefore, requires appropriate cooling and lubrication during machining. With the help of SEM and line-scan EDS analysis, the current study focuses on analysing various sustainable machining techniques, such as electrostatic minimum quantity lubrication (EMQL) and liquid carbon dioxide (LCO2 cryogenic coolant), while drilling Ti6Al4V ELI (Grade 23) holes in terms of hole surface quality, wear mechanisms, and chip morphology. Poor surface quality of the hole was produced under EMQL cutting, with around 42–71% larger surface roughness values (Rz) compared to cryogenic LCO2 conditions. The hole surface consisted of different defects such as adhesion, microfractures, smearing etc., as a residue of the drilling operation under both EMQL and cryogenic LCO2 conditions. Tool life was significantly improved under LCO2 cutting environment (approximately by 416%) in comparison with EMQL technique. Adhesion and abrasion were found to be the main tool wear modes. Likewise, the machined chips exhibited cracks and adhered particles further demonstrating that EMQL coolant did not provide sufficient lubrication and heat extraction capability. Cryogenic LCO2 coolant outperformed EMQL lubrication for all machinability indicators, according to the study, making it a superior cutting environment for machining Ti6Al4V. Moreover, cryogenic LCO2 coolant dissipates into air during the machining process rendering it a sustainable and environmentally friendly machining coolant fluid.

Effect of In-process Cryogenic Cooling in the Burnishing Process on the Solid Particle Erosion Behavior of HVOF Cermet Coating

Effect of In-process Cryogenic Cooling in the Burnishing Process on the Solid Particle Erosion Behavior of HVOF Cermet Coating