Cold cracking in the heat affected zone of a high strength steel weld can take place because of the (A) Retained austenite (B) Martensite formation (C) Relatively high sulphur content in the base metal (D) Sufficient hydrogen present in the welding arc

Cold cracking in the heat affected zone of a high strength steel weld can take place because of the
(A) Retained austenite
(B) Martensite formation
(C) Relatively high sulphur content in the base metal
(D) Sufficient hydrogen present in the welding arc
by

1 Answer

Answer :

(B) Martensite formation
by

Related questions

Steels with high carbon equivalent have poor Weldability, because in these steels during welding (A) Carbon and other alloying elements get oxidised from the weld pool (B) Excessive ferrite forms in the heat affected zone leading to poor toughness of the weld (C) Martensite forms in the heat affected zone leading to poor toughness/ductility of the weld (D) Segregation of carbon and other element occurs in the weld pool leading to poor properties of the weld

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Maraging steels derive their strength from the following mechanism: (A) A fine, highly dislocated and strong martensite (B) Fine dispersions of inter-metallic of Fe, Ni, Ti etc (C) Fine dispersions of alloy carbides in a ferrite matrix (D) Fine dispersions of Fe3 C nucleated on dislocations in austenite

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Secondary hardening in steels arises out of the (A) Precipitation of fine alloy carbides at high temperatures (B) Refinement of ferrite grain size by working (C) Decomposition of retained austenite upon heat treatment (D) Precipitation of complex inter-metallic upon heat treatment

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