In spot welding of aluminium sheets, the welding current should be .........A........ and weld time should be kept ............B......... than for $$MS$$ sheet of same thickness.

(A). higher / lower, (B). higher / lower

....................... is the non-fusion method of joining dissimilar metals with metals whose melting temp is greater than $${400^ \circ }C$$.

High alloy steel components are preheated before welding for reducing

In $$TIG$$ welding a ...........A. .......... and ..........B.......... electrode is used.

A. non-consumable / consumable
B. coated / bare