§2—6材料在拉伸和压缩时的力学性能 Ⅱ低碳钢试样的拉伸图及其力学性能 1, Load-deflection diagram in tension about mild steel mild steel(软钢)=低碳钢P (ow-carbon steel) 如Q235号钢 Characteristic 1,弹性阶段 Elastic range; 2,屈服阶段 Yield range; 3,强化阶段 Hardening range; 4,颈缩阶段 Necking range tensile diagram(P△L) △l o—- diagram 8 P=AMmild steel（软钢）＝低碳钢 (low-carbon steel) 如Q235号钢 Characteristic: 1,弹性阶段Elastic range; 2,屈服阶段Yield range; 3,强化阶段Hardening range; 4,颈缩阶段Necking range §２－6材料在拉伸和压缩时的力学性能 Ⅱ. 低碳钢试样的拉伸图及其力学性能 l l A P D = = e s 1,Load ——deflection diagram in tension about mild steel: tensile diagram(P——△L) s −−e diagram: