EVALUATION OF MICRO STRUCTURAL AND MECHANICAL PROPERTIES OF DISSIMILAR TIG WELDED INCONEL AND SS304 JOINTS

In industry most of the materials are fabricated into the desired shape mainly by one of the following methods viz. casting, forming, machining and welding. The selection of a particular technique depends upon different factors which may include shape and size of the component, precision required, cost, material and its availability. Sometimes one specific process may be used to achieve the desired object. However, more often it is possible to have a choice between the processes available for making the end product.

Dissimilar combinations of Inconel 625 alloy and SS 304 weldments have been widely used in versatile engineering applications such as aerospace engine components, chemical processing equipment, oil and gas industry and power plants. 

Inconel 625 alloy exhibits extraordinary resistance to oxidation and corrosion at elevated temperatures. Similarly, austenitic stainless steel, SS 304, has better corrosion and oxidation resistance due to higher amounts of Cr, Ni and Mo.

In this project, an investigation will be made on dissimilar welded joints of SS304 along with Inconel 625 using TIG (Tungsten inert gas welding) process. In particular these materials are more suitable for high temperature applications and act as anti-corrosive material, where Inconel 625 are rich in chromium content, suitable for high corrosion resistance. ER80S-D2 filler rod is used for the joining of these two materials. The mechanical behavior of the weld joint like hardness and tensile characteristics has been examined and corrosion resistance of the weld joint can be identified using salt spray corrosion test.

Tests conducted:

• SEM analysis
• Micro structure on HAZ
• Micro structure on weld 
• Hardness test
• Tensile tests
• Corrosion tests

Cost of the Project:

Rs. 20000 /-