Remanufacturing is a process of returning a used product to at least its original performance with a warranty that is equivalent or better than that of a newly manufactured product. During a preliminary inspection on remanufacturing companies, it was found that there is no end life for crankshafts in terms of classifying it either to remanufacture, repair or reject due to limited information provided by the original equipment manufacturer. The manufacturer did not provide any information on the annual quantity produced and their specifications to the remanufacturing company for the purpose of referencing. Eventually, the distinctiveness of the remanufactured crankshaft from the original cannot be measured. Thus, the aim of this work is to classify crankshafts' end life into recovery operations based on the Mahalanobis-Taguchi System. The crankpin diameter of six engine models were measured in order to develop a scale that represents their population in a scatter diagram. It was found that on the diagram of each engine model, the left distributions from the center point belong to rejected crankshafts, the right distributions belong to re-manufacturable crankshafts, and the upper distributions belong to the repairable crankshafts. The developed scale is believed to be able to help remanufacturers instantaneously identify and match any unknown model crankshafts to its right category. The Ministry of International Trade & Industry (MITI) has established a remanufacturing policy under RMK11 and put in efforts to encourage Malaysians to venture into the remanufacturing business. Thus, this model will help the industry to understand and formulate their decision-making to sustain the end of life of their products.

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Open cell foams, made on the basis of polyurethane foams replication method are well known and had been widely used since decades. The advantage of the network-like metal foams is it exhibits a natural bone-like structure which enables ingrowth of bone cells and blood vessels. The aim of the present study is to develop SS316L foam with an open cell structure by using powder metallurgy routes via foam replication method. The SS316L slurry was produced by mixing SS316L powder with Polyethylene Glycol (PEG), Methylcellulose (CMC) and distilled water. The composition of the SS316L powder in the slurry was varied from 40 to 60 wt. %. Then, polymeric foam template was impregnated in SS316L slurry and dried at room temperature. Sintering was carried out in a high temperature vacuum furnace at 1300°C. The microstructure of the SS316L foam produced was observed by Scanning Electron Microscope (SEM) and the elemental analysis was carried by Energy Dispersive X-ray (EDX). It was found that pore size are within 200-400μm and the average pore size is 293μ. The detected elements in the SS316L foam were C, Al, Ca, O, Cr, Fe, Mo, Ni and Si.

Metal foams are well-known as engineered materials with unique combination of physical and mechanical properties, yielding an attractive material for use in the aerospace industry, automotive and medical industry. In this study the method that been used to produce SS316L foam is slurry method. Slurry of stainless steel is prepared by mixing binder material such as methyl cellulose (CMC), polyethylene glycol (PEG) and distilled water by using ball milling machine. Then, the sample is sintered at different temperatures which are 1300°C, 1350°C and 1400°C. The value of porosity and density of SS316L foam are collected utilizing Archimedes method. As the result, the porosity percentage found in the range of 4.77 % to 59.80% meanwhile density value ranging from 0.402g/cm3 to 0.952g/cm3. The highest value of porosity is 59.80% at 1300°C for 40wt% SS316L, while, the highest value of density is 0.952g/cm3at 1350°C for 60wt% SS316L. These results was followed the theory of porosity and density which are the value of porosity is inversely proportional to the density.

Metal foams are widely produced by using different techniques such as compaction and replication method. In this study, slurry method also known as replication method has been used to produce SS316L foams. SS316L powders (50wt% and 60wt%) were mixed with the binders and distilled water by using mechanical stirrer. Polyethylene Glycol (PEG) and Carboxyl Methyl Cellulose (CMC) were used as binders. Polyurethane (PU) foam was used as scaffold and dipped into SS316L slurry then dried in room temperature for 24 hours. Sintering process has been done in two different temperatures which were 1200°C and 1300°C in vacuum furnace. The morphological study was performed using Scanning Electron Microscopy (SEM) and Energy Dispersive X-Ray (EDX). The SEM micrograph showed that the cells were interconnected and the structures become denser as the sintering temperature increase. The average pores size is ranging from 252.8 μm-353.8 μm, while strut size ranging from 50.2 μm-79.9 μm based on SEM micrograph analysis. The elemental analysis from EDX showed the element presence in the SS316L foam remain from SS316L powder which are Chromium (Cr), Nickel (Ni), Molybdenum (Mo), Cooper (Cu), Nitrogen (N2), Sulphur (S) and Silicon (Si). Higher sintering temperature contributes better grain growth between particles where the point-contact between the particles expanded and disappear the small pores.