Additive Manufacturing technique has the capacity to fabricate 3D parts with complex geometries, but these parts contain some defects, including increased roughness, poor quality, and poor fatigue life. These defects have resulted from balling effects, staircase effects, and incompletely fused, leading to irregular morphologies of surfaces. These irregular morphologies result in the poor or deteriorated performance of the structures, limiting their applications. The post-treatment techniques have been developed to improve the surface quality of AM parts. In this review, different technologies of surface finishing methods, including chemical, mechanical and thermal-based methods depending upon the method of removal of material, are discussed. The advancements in the techniques are highlighted, and the results obtained from different experimental studies involving different categories of finishing and polishing of the AM parts are compared and discussed in this paper. Different opportunities and challenges to maintain and control the surface roughness of the additively manufactured components of the metallic substances are addressed. Graphical Abstract

Recent advances in technology and refinement of available computational resources paved the way for the extensive use of computers to model and simulate complex real-world problems difficult to solve analytically. The appeal of simulations lies in the ability to predict the significance of a change to the system under study. The simulated results can be of great benefit in predicting various behaviors, such as the wind pattern in a particular region, the ability of a material to withstand a dynamic load, or even the behavior of a workpiece under a particular type of machining. This paper deals with the mathematical modeling and simulation techniques used in abrasive-based machining processes such as abrasive flow machining (AFM), magnetic-based finishing processes, i.e., magnetic abrasive finishing (MAF) process, magnetorheological finishing (MRF) process, and ball-end type magnetorheological finishing process (BEMRF). The paper also aims to highlight the advances and obstacles associated with these techniques and their applications in flow machining. This study contributes the better understanding by examining the available modeling and simulation techniques such as Molecular Dynamic Simulation (MDS), Computational Fluid Dynamics (CFD), Finite Element Method (FEM), Discrete Element Method (DEM), Multivariable Regression Analysis (MVRA), Artificial Neural Network (ANN), Response Surface Analysis (RSA), Stochastic Modeling and Simulation by Data Dependent System (DDS). Among these methods, CFD and FEM can be performed with the available commercial software, while DEM and MDS performed using the computer programming-based platform, i.e., “LAMMPS Molecular Dynamics Simulator,” or C, C++, or Python programming, and these methods seem more promising techniques for modeling and simulation of loose abrasive-based machining processes. The other four methods (MVRA, ANN, RSA, and DDS) are experimental and based on statistical approaches that can be used for mathematical modeling of loose abrasive-based machining processes. Additionally, it suggests areas for further investigation and offers a priceless bibliography of earlier studies on the modeling and simulation techniques for abrasive-based machining processes. Researchers studying mathematical modeling of various micro- and nanofinishing techniques for different applications may find this review article to be of great help.

This study explores the use of Polypropylene (PP) as a cost-effective matrix in composite materials, employing marble dust (MD) as a readily available filler. PP’s affordability and suitable strength make it ideal for various applications. MD, composed of CaCO₃, alumina, and silica, enhances mechanical strength and is commonly used in construction applications like concrete. Composite specimens were fabricated using the injection molding technique, and their mechanical properties (tensile, flexural, and compressive strength) were analyzed following ASTM standards. Tribological properties were assessed through a pin-on-disc apparatus with varying MD proportions. SEM and EDS analyses visually inspected the fracture types and filler distribution in the composites.