The Effect of Pulsed Nd:YAG laser on some properties for NiTi with 304L Austenite stainless steel

Dissimilar welding of austenitic stainless steel AISI 304L to shape memory alloy SMA NiTi was conducted by utilized Nd: YAG laser beam welding technique. Both AISI 304 Austenite stainless steel and Shape memory alloy have the same dimension (80*20*0.5) mm. The experimental investigation included, micro-hardness and microstructure. The better laser parameters in this research (peak power of (2.25 KW), pulse duration of (2.4 ms), pulse repetition rate of (40 Hz), and welding speed of (8 mm/Sec). The results demonstrate that the Vickers microhardness of weld area begin to decline until it reaches the base metal because formation brittle intermetallic compound in the welding zone. SEM with optical microscope demonstrate the solidification method along the fusion area various in different joints, where they become the planer shape to cellular and transformed the last to dendritic from intra-fusion welding area toward the center because towards weld area interface to weld centerline cooling rate will be rise in all Shape Memory Alloy (NiTi) and Austenite Stainless Steel sides.

Keywords:

Nd:YAG laser , NiTi , Shape memory alloy , Austenite Stainless steel