Study on the Type of Friction Welding (Report 2)

Friction Welding of Stud to Plate

Abstract

In the previous report, difference between brake type and inertia type friction welding was discussed, then effect of various parameters on burn-off behaviours and macrostructures of the same diameter bar friction welds was studied. Deceleration condition of rotation was shown very effective parameter.
In this report, friction welding parameters and joint design for the welding of stud to plate joint was considered.
Experimental results were as follows;
1) Friction welding of stud to plate joint was relatively difficult than welding of same diameter bar joint, because some characteristic defects caused by the shape effect was appeared. So, the parameters of higher pressure and longer deceleration time should be used for the stud to plate joint than those for same diameter bar joint.
2) When same welding condition was used for both stud to plate and same diameter bar joint, the former showed rather convex shape heat affected zone.
3) Heat affected zone of stud to plate joint became narrower and concave shape with increase of pres-sure and deceleration time similarly the case of same diameter bar joint.
4) Movement of friction surface from the plate face to stud was occurred when low pressure was used for stud to plate joint. And moved zone was difficult to be removed only by using high upsetting pressure.
5) Protrusion should be prepared when frictoin pressure was restricted to the low level.