The proper preliminary heat treatment for T12 steel is . A: complete annealing B: homogenizing annealing C: spheroidizing annealing D: isothermal annealing

Which sequence is correct according to the procedure of PCR ?() A: denaturation → extension → annealing B: denaturation → annealing → extension C: annealing → denaturation→ extension D: Extension → annealing → denaturation

The cooling rate for normalizing is faster than that of annealing. A: 正确 B: 错误

____is<br/>a low-temperature heat treatment used to eliminate all or part of the<br/>effect of cold working in steels. A: Normalizing B: Spheroidizing C: Annealing D: Process<br/>annealing

To obtain an steel with fine pearlite we perform the commercial heat treatment known as total annealing. A: 正确 B: 错误

Annealing and normalizing present a significant difference on the ductility of low carbon steels.​

The brazing weld need annealing heat treatment so that it is easily machined.。（ ）

To obtain an steel with fine pearlite we perform the commercial heat treatment known as total annealing

PCR<br/>process includes three steps, they are() A: denaturation B: annealing C: extention D: cooling

During heat treatment of steel, austenite transforms into martensite by A: annealing B: austenitizing C: quenching D: normalizing