Resistance microwelding of crossed Pt–10Ir and 316 LVM stainless steel wires

Abstract

Resistance microwelding of dissimilar materials such as Pt-10Ir and 316 low carbon vacuum melted stainless steel is becoming increasingly important for making electrical connections in medical devices. The joining of dissimilar materials increases flexibility in design while providing economic advantages, where more cost effective materials can be substituted for traditional materials. In this work, the performance of joints made using different electrode forces was studied by examining the surface morphology, cross-sections, joint break force and dynamic resistance measurements from resistance microwelding joints. Electrode sticking and excessive expulsion were observed with low electrode forces, whereas joints with undesirable cracks and notches were produced at higher electrode forces. Based on the analysis of single pulse welds, a new process variation using multiple pulses was developed, which improved the weld surface quality while obtaining a joint strength near 90% of the Pt-10Ir wire tensile strength.

Crossed-Wire Laser Microwelding of Pt-10 Pct Ir to 316 LVM Stainless Steel: Part II. Effect of Orientation on Joining Mechanism

“…[14] As a result, the temperature in the MZ may not reach a degree high enough to cause vaporization. Furthermore, the Pt-Ir wire has a thermal diffusivity of 24 times that of SS, [10] leading to higher freezing rates and less time for entrapped gasses to escape via buoyancy forces.…”

“…[1,[5][6][7] As acknowledged in recent publications, variations in resistivity and other material properties have hindered the application of RMW for dissimilar materials. [4,[8][9][10] Therefore, study of dissimilar laser spot microwelding of the preceding materials is worth investigating.…”

A Connection Method between Ultrahard PtW8 Wire and a Au Thick Film Based on Parallel-Gap Resistance Microwelding

“…However, the physical properties of the materials studied are not much different and the joint formation during the bonding process is not clear. In research on the resistance microwelding of crossed Pt-Ir alloy wire and 316 LVM stainless steel wires, Huang et al showed that increasing the wetting of molten metal on the surface of the joint can significantly improve the performance of the joint [ 17 , 18 , 19 ].…”