Abstract

Fatigue failure is one of the main reasons for the mechanical failure in engineering materials. To improve the fatigue strength of the material one of the most used method is heat treatment of the materials in which hardness, wear resistance and aesthetics is improved. Of late, the complexity of predicting fatigue life of engineering components is increasing exponentially due to the varied and multi-facet loading conditions, complex geometries, and newer materials coming up in the market. In this paper the the quantitative measurement of the influence of Annealing on the fatigue life of SS 304 steels. Theresults conculed clearly clearly that there is a definite improvement in the fatigue life due to Annealing in steel. However the extent of improvement in fatigue life was more in SS 304 (after annealing) when compared to SS 304(before annealing).

Stainless steel 316 L is combination of chromium-nickel-molybdenum austenitic stainless steel developed to improve the corrosion resistance better than alloy 304.It also provides higher creep, stress-to-rupture ratio and good tensile strength at elevated temperatures. Machining in Distilled water has given better result at higher MRR and low tool wear rate than in kerosene. The machining accuracy was not very good but the surface finish was slight better. This paper deals with the optimization and analysis of the EDM process of SS 316L. The Taguchi method was used to determine the combination of EDM process parameters like current, pulse ON, pulse OFF, Voltage which minimize surface roughness and maximize hardness of the material. The experiments were planned & performed as per L9 orthogonal array (OA) and signal-to-noise (S/N) ratio was applied to determine the proposed performance characteristics.

Titanium and its alloys are the most commonly and most widely used due to its significant properties like good biocompatibility , good tensile strength , low density , and good creep property up to 300 degrees centigrade .It is used in the major engineering fields like civil engineering , nuclear engineering , aerospace engineering etc., but the welding of titanium in industries has become a major challenging objective to the fabricators because, a lot of titanium alloys are found in the form of sheets , problem arises mainly while fabricating the space crafts , marine bodies , jet engine’s where the ends are need to be joined through welding with a similar or dissimilar metals and titanium possess to have a very high tendency to oxidize at higher temperatures .As Titanium becomes highly reactive to chemicals in its environment. In regular air, welding contaminates titanium with carbides, nitrides, and oxides that make the weld and HAZ (heat-affected zone) brittle, resulting in lower fatigue resistance and notch toughness. so, In order to get a perfect weld it is very important to avoid the molten metal to the exposure of atmospheric air , which will lead to porosity and results into a poor welding conditions or welding defects. This paper reviews the different methods of welding titanium and its alloys.