Ball-end magneto-rheological finishing (BEMRF) process is a variant of magneto-rheological finishing (MRF) which is capable of finishing magnetic as well as nonmagnetic materials to finish surfaces up to the order of nanometers. The development of this process has been fairly recent and the literature has focused on quantifying and analyzing the effects of finishing on different materials with it. This research work presents a time-based roughness reduction study of BEMRF process to find out the behavior of machining parameters in finishing over lengthy time intervals. EN31 steel has been chosen as the work material for this study. Firstly, a machining parameter optimization is carried out for finishing of EN31 steel with BEMRF process. A detailed time-based experimental study is then carried out to find the effect of time on finishing with BEMRF process. The time-based study revealed a transient roughness reduction phenomenon in which a particular set of machining parameters was capable of reducing the surface roughness only up to a limited roughness value. The study concluded a database for finishing of EN31 steel with BEMRF process which can be used for optimum time-based finishing with BEMRF process.

Ball end magnetorheological finishing (BEMRF) is a process employed for precision finishing of flattened, intricate form complex 3D surfaces up to the nano level. Roughness of a surface determines the quality of results produced, which is usually measured by stylus-based instruments, with some optical methodologies also being adopted. These conventional methods when used for BEMRF tend to introduce errors in the part, which have to be removed from its fixture for measurement, and it is not feasible to remount it in the exactly same orientation again. Applications such as insular finishing (i.e., confined to a narrow region on the workpiece) demand the workpiece to be kept in the same orientation throughout, leading to requirement of measuring roughness in situ during the BEMRF process. A confocal sensor fits the requirement because of its confined design and lightweight capabilities. This work presents integration of a confocal sensor into the BEMRF setup for in situ roughness measurement. An initial Ra value of 352 nm was reduced to 289 nm just by insular finishing before finishing the full surface down to 78 nm in the case of a grinding error, from 420 nm to 342 nm by insular finishing, and finally down to 142 nm in the case of lapping error.

Shape memory alloys (SMAs) have garnered substantial attention due to their remarkable properties and diverse applications with 3D printing techniques. The present work comprehensively reviews 3D printing applied to various SMAs. The paper examines different 3D printing techniques for SMAs and discusses the process parameters crucial for printability. The potential of 3D printing SMAs lies in the ability to create complex geometries and customized designs that are unattainable through conventional manufacturing methods. Thus, 3D printed SMAs are used across diverse fields, including biomedicine, aerospace, engineering, and consumer goods. While recognizing the notable progress achieved, the review addresses ongoing challenges such as attaining consistent microstructures, post-processing and cost-effective production. It also highlights future prospects, including the development of new SMAs compositions, and expanded applications in various other fields. As a result, the review offers a succinct and comprehensive report on SMAs using 3D printing, which could serve as a useful resource for scientists, engineers, researchers, and industry in their future work.