苏辉!沈阳市110006
,
张玉贵
,
阎振棨
材料研究学报
借助分形研究了拉伸条件下,分形维数D_F 与拉伸性能之间的关系,讨论了显微组织对分形维数的影响,并把冲击韧性与分形维数之间的关系和拉伸性能与分形维数之间的关系进行了比较。实验结果表明,拉伸性能与分形维数只存在定性关系。延伸率与分形维数成正比,强度σ_b、σ_s与分形维数成反比,显微组织对分形维数有重要影响。断裂方式对分形维数、断裂性质以及两者的对应关系也有重要影响。
关键词:
分形维数
,
yardstick
,
microstructure
,
tensile property
,
fracture feature
沈显璞
,
王继业
,
杨德庄
,
R.PRIESTNER
金属学报
本文研究了硼对低碳低合金钢经(α+γ)区加热形成的奥氏体的淬透性的影响。结果表明,增加硼含量(从0.0005到0.0029％),将减少亚温区加热时形成的奥氏体含量。但明显增加了奥氏体的淬透性,并且降低了马氏体含量及钢的拉伸性能对冷却速度变化的敏感性。同位素示踪分析表明,在亚温区加热时,硼原子仍明显分布在原正火态奥氏体晶界上,没有见到硼原子向α/γ相界的迁移和偏聚。
关键词:
双相钢
,
boron
,
hardenability
,
tensile property
蒋晓军
,
李依依
,
师昌绪
金属学报
本文研究了两种不同量的Ag的加入对自然时效状态Al-Li-Cu—Mg—Zr合金在290—77K温度范围内的拉伸性能及断裂行为的影响。结果表明,随着实验温度的降低,合金的拉伸性能在153—77K之间明显改善,不含Ag合金的延伸率则基本保持不变;所有合金在室温时的变形与断裂模式基本相同,主要为平面滑移引起的穿晶剪切断裂;但低温下的拉伸行为随Ag的加入而表现出不同的特点,即含Ag合金的变形在低温下趋于均匀,其低温延伸率的改善可归因于此;低温下合金分层及沿晶开裂的倾向增加
关键词:
Al-Li合金
,
tensile property
,
fracture behaviour
,
minor additions
,
Ag
B.Y. Yu*
,
C.L. Bao
,
H.W. Song
,
Z. Liu
金属学报(英文版)
The effect of extrusion ratio on microstructures and mechanical properties of magnesium alloy AZ91D extruded tube at 430℃ has been studied. After the evolution of microstructure and mechanical properties of AZ91D during extrusion were studied, the following parameters were obtained: tensile strength reached the climax value of 306.9MPa and elongation peak value of 10.1% at an extrusion ratio of 7.125, and with the increase of the extrusion ratio to 7.45, yield strength reached a top value of 285.795MPa with decreased tensile strength and elongation. It was concluded that mechanical properties of magnesium alloys AZ91D could be enhanced by adjusting the extrusion ratio near recrystallization.
关键词:
magnesium
,
挤压
,
管材
,
组织
,
力学性能
