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in the first 48 h of natural aging. The electrical conductivity of 7050 alloy in natural aging state is determined by the size and density of GP zones, and the size of GP zones is the main factor. After natural aging for 70 d, the size of GP zones is 1.8-2.6 nm in matrix of the immersion quenched sample and it is 1.4-1.8 nm in matrix of both water mist and forced air quenched samples. After......
模压变形5052铝合金的显微组织与室温拉伸性能杨开怀1,2,曾建民1,邹泽昌2,陈文哲31. 广西大学广西有色金属及特色材料加工省部共建国家重点实验室培育基地2. 福建船政交通职业学院机械工程系3. 厦门理工学院摘 要:对5052铝合金板进行了多道次模压(GP)变形,研究了GP变形道次对其显微组织和室温拉伸性能的影响.结果表明:该铝合金的平均晶粒尺寸随GP变形道次的增加而减小,4道次变形后平均晶粒尺寸由未变形的43.2μm细化到约1.1μm;抗拉强度随GP变形道次的增加而单调递增,伸长率则先快速下降后缓慢升高;4道次GP变形能使5052铝合金在提高抗拉强度的同时保持良好的塑性.关键词:模压变形;5052铝合金;显微组织;拉伸性能;......
spectroscopy (EDX) analysis indicate that the precipitation sequence of η phase along low-angle grain boundaries should be supersaturated solid solution (SSS)→vacancy-rich clusters (VRC)→GP II zones→η′→η... by the diffusion of the solute-vacancy complex during aging treatment. The grain boundary segregation plays an important role in the nucleation and growth of VRC, GP II zones, η′ phase as well as η......
→FCC富Cr的GP区(Ⅰ)→FCC有序富Cr的GP区(Ⅱ)→BCC有序富Cr相.在脱溶演变过程中,析出相和基体之间的界面由完全共格界面向共格-半共格界面转变,位向关系由立方-立方向Nishiyama-Wassermann位向关系转变.共格界面的形成有利于FCC富Cr相的形成.富Cr析出相的有序化加速析出进程,并有利于BCC相的形成,促进了Nishiyama-Wassermann位向关系的发展...-Zr-Mg alloy aged at 450 ℃ is supersaturated solid solution → solution segregation → GP zone (Ⅰ) (FCC Cr-rich phase) → GP zone (Ⅱ) (ordered FCC Cr-rich phase) → ordered BCC Cr-rich phase......
分析手段研究C17200合金时效过程中微观组织演变,测试不同时效工艺处理后合金的硬度和电导率等性能.结果表明:合金经320 ℃时效1 h后,基体(200)主峰的左侧出现比较明显的低角度边带峰,即合金发生调幅分解,使得在基体的(100)面上形成圆盘状结构的GP区.合金在时效过程中存在两种析出方式:晶界不连续析出和晶内连续析出,且连续析出序列为α过饱和固溶体→GP区→γ′→γ.调幅分解和γ′相析出是... processes were also tested. The results show that after the alloy was aged at 320 ℃ for 1 h, low angle side-band peak is observed at the left side of (200) peak of the matrix, and disk-like GP zones form......
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="ChDivSummary" name="ChDivSummary">The compressive strength of mortar containing glass powder(GP) and/or glass aggregate(GA) was tested, and its microstructure was also studied by thermogravimetric... the compressive strength of the mortar in the absence of GP. Incorporating both GA and GP could change the hydration environment, promote pozzolanic reaction of GP and improve the compressive strength. GP......
7050铝合金双级双峰时效沉淀相的析出过程及作用何昌德1,任建平1,徐兵1,杨普新21. 台州科技职业学院机电工程系2. 中国吉利汽车研究院摘 要:研究了7050铝合金双级双峰时效的第二级时效时沉淀相的析出过程及作用.结果表明:合金在第二级时效的硬化第一峰主要由细小,均匀的GP区贡献,而第二峰由晶内细小的η′相与粗大GP区共同作用,后者的强化效果要优于前者的;第二峰峰值时析出的η′相细小均匀地分布于晶内,间距非常小,体积分数较大,GP区粗大;随着时效进一步深入,晶界上的η′相开始聚集粗化,开始转变为平稳的η相,GP区消失.关键词:7050铝合金;双级双峰时效;沉淀相析出;......
Al-Zn-Mg-Cu合金时效沉淀相应变场研究刘飞,白朴存,侯小虎,赵春旺,邢永明内蒙古工业大学摘 要:利用高分辨透射电子显微镜研究喷射成形Al12Zn2.4Mg1.1Cu合金不同时效时间析出的GPⅡ区和η′亚稳沉淀相,并结合几何相位分析软件计算了GPⅡ区和η′亚稳沉淀相的应变场.研究表明:该合金的时效硬度变化和主要析出相的变化密切相关.GPⅡ区大量弥散析出是造成合金硬度迅速上升的主要原因.η′是峰值时效状态下的主要析出强化相.析出相从GPⅡ区到η′的转变,是应变峰值较小的分散半共格应变场取代了应变峰值较大的集中共格应变场的过程.并对GPⅡ区和η′亚稳沉淀相的演变过程及强化机制进行了讨论.关键词:应变;沉淀相;几何相位分析软件;高分辨透射电子显微术;......
强化相的尺寸和含量均增加,且有利于慢速冷却处形成数量更多,分布更均匀弥散的GP区,硬度升高明显,淬火敏感性很低.自然时效时间长达17 280 h；该合金的沉淀强化相为GP区,未发现η′相. 关键词:Al-Zn-Mg-Cu合金；淬火敏感性；自然时效 中图分类号:TG146.21 .... With the increase of the natural aging time, the size and volume fraction of hardening precipitates increases, and therefore hardness increases obviously. Moreover, a larger amount of dispersive GP zones can form......
