A.淬火、人工時(shí)效 B.淬火、自然時(shí)效 C.退火、自然時(shí)效 D.退火、人工時(shí)效
A.30° B.60° C.90°
A.70°~80° B.90°~100° C.116°~118° D.130°~140°