国产精品成人3p一区二区三区 -亚洲经典自拍-日韩电影在线观看网站-精品一区二区三区视频在线播放-日韩一区三区-伊人久久亚洲影院

Canggu protection box strength: strength refers to the resistance of metal materials to deformation or fracture under the action of external forces. The strength index is an important basis for determining the allowable stress in the design. The commonly used strength indexes are the yield strength σS or σ0.2 and the tensile strength σb. When working under high temperature, the creep limit σn and the durable strength σD should also be considered.

Canggu protection box Plasticity: Plasticity refers to the ability of metal materials to undergo plastic deformation before fracture. Plasticity indicators include: elongation δ, that is, the relative elongation after the specimen is pulled off; the area shrinkage ratio ψ, that is, the relative reduction in the cross-sectional area of the pull-out area after the specimen is broken; cold bending (angle) α, ie The test piece was bent to the angle measured when the first crack appeared on the tensile surface.