Weldability of Cr Stainless Steel Plates (Report 4)

An experiment on the brittleness of welded 18Cr steel plate

Abstract

V-butt multi-layer welding of a 18Cr steel plate, 7., 5mm thick, has been carried out with three kinds of austenite electrodes (AlSl type 308, 316 and 310) and one kind of ferrite-austenite electrodes (all of them, 4mm diameter). The obtained welds have been subjected to a hardness test, microstructu-re test, V-notch Charpy impact test at -200-+300°C; fractographs of the brittle-fractured surfaces in their impact fractures have been examined and some considerations made on them.
Some of the major results are summarized :
1) Transition temperature in the non-affected and the heat-affected zone of parent metal is very high. It is higher in the latter than in the former ; in the latter no annealing effect is observable.
2) Impact value of welds using ferrite-austenite electrodes are in general lower than those of the ones using austenite electrodes. However, excessive lowering of these values does not take place on low temperature side.
3) Fractographs of brittle fractures in the impact fractures of the heat-affected, non-affected zones of parent metal and of welds have been studied to seek the relationship to ductility.