This review article offers consolidated knowledge on the subject of several traditional and non-traditional procedures that are taking place throughout the years to form shape memory alloys (SMAs). At the primary part of the review, the usage of several shape memory alloys was shown. The dialogue then continued towards numerous traditional techniques of operating followed by the obstacles in the running of SMAs utilizing traditional techniques of operating. Moreover, numerous non-traditional processes of operations such WJM (Water jet Machining), cryogenic, WEDM (Wire Electro Discharge Machining), EDM (Electro Discharge Machining), and electrochemical machining explored. As well, Numerous of outcomes reactions that may occur during the operation procedures have been emphasized such as material removal rate (MRR), rate of tool wear, surface roughness (SR), the surface integrity. A consolidated records of various academics and their findings on this issue has been evaluated. After all, the article has been concluded by suggesting a variety of key points seen throughout the review process.
Understanding the process of tool wear in the initial and steady wear stages is crucial for ensuring the dimensional accuracy and surface quality of the workpiece, especially during the finishing step. In order to improve the tribological and tool life behaviors when machining the AA2024-T351 alloy, the current paper focuses on the potential use of cryogenic cooling conditions. Here, the experiments were performed under dry, minimal quantity lubrication (MQL), liquid nitrogen (LN2), carbon dioxide (CO2), conditions. The critical tool wear factors in terms of geometrical aspects and physical phenomena were investigated under sustainable cooling environments. The results prove that cryogenic cooling is helpful in improving tool life with good tribological characteristics.
Nanofluids are a unique class of fluids generally prepared by adding nanosized particles to different types of base fluids, such as water, oil, etc. When nanoparticles are added to the base fluids, their thermophysical parameters like viscosity, heat transfer characteristics, and thermal conductivity are improved and provide good results. For this reason, the demand for fluids enriched with nanoparticles has considerably increased in the manufacturing sector. This comprehensive state-of-the-art review covers nanolubricants' role in friction reduction, wear resistance, and machining efficiency applications. Initially, the lubricants and their properties are revealed in the introduction section. Then, the different types of nanoparticles, their basic structure, and their different applications in machining and tribology are portrayed in different sections. In addition, it provides a comprehensive analysis of the difficulties related to nanofluids and their utilization in machining and tribology. Ultimately, this evaluation provides final comments on the latest advancements in both the academic and industrial sectors, as well as a strategy for future expansion. The results indicated that the fluids loaded with nanoparticles had a beneficial effect in lowering friction and temperature at the primary contact zone.
Abstract Simulation modelling methods have gained dramatic acceleration in the last years among academic environments and industry-driven enterprises. Primary reason is that such models have great potential in predicting of machining process parameters. Therefore, tis study evaluates the place and capability of these models in fundamental machining operations. In this direction, Finite Element Modelling Methods are discussed by questioning their contributions to the process performance. Despite numerous positive aspects, development of a successful model is highly difficult owing to the complexity of machining environment with variation of thermo-mechanical effect, tribological conditions, interaction of process variables and high deformation rate of materials etc. Therefore, a critical assessment of the merits and drawbacks of each method associating with their basic phenomena has been investigated. Predictive models basically aim to estimate the machinability characteristics such as stress–stain rates, cutting forces and temperatures etc. Nevertheless, practical applications require correlations between these characteristics and performance outcomes such as surface integrity of part, tool wear index, chip morphology, dimensional accuracy etc. In the end, the molecular dynamics and smoothed particle hydrodynamics have been discussed. Thus, this paper is expected to contribute to up-to-date studies by criticizing the key findings of the predictive models in machining processes.
Although chip morphology changes according to the machining method and related cutting parameters, chip formation affects the quality of the machined surface. In this context, it is very important to understand the relationship between chip morphology and surface quality, especially in materials that are difficult to machine. In the presented study, the changes in chip morphology, surface morphology, and surface quality criteria (Ra and Rz) that occurred during the milling of precipitation-hardened steel in different cutting environments were analyzed. Milling experiments were carried out in dry, MQL (minimum quantity lubrication), nano-MQL (graphene), nano-MQL (hBN), Cryo, and Cryo-MQL environments using TiAlN-coated inserts and three different cutting speeds and feed rates. While the highest values in terms of Ra and Rz were measured in dry machining, the minimum values were obtained in a nano-MQL (hBN) cutting environment. Due to the lubrication and low friction provided by the MQL cutting environment, chips were formed in thinner segmented forms. This formation reduced the chip curve radius and thus provided a more stable surface morphology. On the other hand, Cryo-ambient gas could not effectively leak into the cutting zone due to the intermittent cutting process, but it increased the brittleness of the chips with the cooling effect and provided a similar surface morphology. The values of minimum Ra and Rz were obtained as 0.304 mm and 1.825 mm, respectively, at a 60 m/min cutting speed and 0.04 mm/rev feed. Consequently, the use of nano-MQL cutting medium is seriously recommended in terms of surface quality in milling operations of difficult-to-machine materials.
In-process measurements are becoming more and more popular among businesses as a result of the numerous benefits they provide, including reduced production costs, improved product quality, and real-time analysis of both production and product quality of aerospace materials. It is anticipated that the method of measuring manufactured components known as "in-process measurement" will become the standard practice in the not too distant future. After a description of the in-process measurement methods with the developed examples, an explanation of the usage of machine tools as a measurement device will be provided in this paper, along with the needs, issues, and challenges, and recent research work.
