H. Zhang
,
Y. Y. Liu
,
D. S. Peng and C. K. Wang (Department of Materials Science and Engineering
,
Central South University of Technology
,
Changsha 410083
,
China)
金属学报(英文版)
Continuous thermo-mechanical processing (CTMP) of 6201 aluminum alloy was simulated on Gleeble-1500. The deformed specimens were analyzed by the observation of TEM and the measurement of hardness. It was shown that rapid solid solution and aging treatment can be effectively combined in one procedure by the strain induced during CTMP. The deformation temperature is ranging from 540* C to 300* C, the hardness increases directly before the 6th pass followed by a slight drop, the amount of precipitates increases with the holding time after deformation. Uniformly distributed and stabilized Mg2Si precipitates, as well as dislocation substructure can be observed on deformed specimens which have been subsequently held at 300℃ for 60 seconds.
关键词:
6201 aluminum alloy
,
null
,
null
,
null
,
null
K.K. Zhang
,
D.R. Chen
,
J. Xue
,
D. W. Sun and H.C. Li( 1) Department of Materials Engineer
,
Xi'an Jiaotong University
,
Xi'an 710049
,
China 2) Luoyang Institute of Technology
,
Luoyang 471039
,
China 3) CITIC Heavy)
金属学报(英文版)
Base on a vast amount of testing and calculations for the welding thermal cycling curves of different testing points in fusion welding (TIG welding, gas welding) HAZ of zinc-based alloy with low melting points, this paper defines the welding thermal cycle parameters of microstructure stimulation of HAZ by zinc-based alloy fusion welding process. On the principle of which the microstrnct,are and harkness of the testing points in simulation specimens are basically correspondence with that of actual welding HAZ, the microstructure simulation of testing points Tm=370O℃. 305℃) of ZA12 alloy by fusion welding is carried out by the means of omhic-heating welding thermal simulation tester. The study results of the abrasion-resistance of simulation specimens HAZ by fusion welding process indicates that the abmsion-resistance is closely related to the form of eutectoid microstructure in or in the structure.
关键词:
zinc-based alloy
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null
,
null
,
null
,
null
张德芬
,
王进
,
李烨铮
,
景亮
材料热处理学报
利用Gleeble热模拟试验机模拟研究了X80钢焊接热影响区粗晶区组织在不同冷却速度下的变化规律,研究了冷却时间、组织和性能之间的关系.结果表明,X80钢焊接热影响区粗晶区组织主要由板条贝氏体和粒状贝氏体组成.随冷却时间t8/5时间增加,板条贝氏体含量逐渐减少,由细长状转变成粗大片状、并趋于平行;粒状贝氏体含量逐渐增加,其间的马氏体M/奥氏体A组元数量增加,间距缩短,面积增大.随冷却时间t8/5时间增加,焊接热影响区粗晶区冲击韧性先增加后减小;当t8/5=7 s时,X80钢焊接热影响区粗晶区组织为少量的粒状贝氏体,且弥散分布于大量板条贝氏体之间,细化板条贝氏体,增加有效晶界,起到细化和强化作用,冲击断口分布着大量的细小韧窝,为明显的韧性断裂.
关键词:
X80钢
,
热模拟
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焊接热影响区粗晶区
,
贝氏体
,
冲击韧性
孙磊磊
,
柏明卓
,
郑磊
钢铁
doi:10.13228/j.boyuan.issn0449-749x.20130713
铁素体-贝氏体双相组织钢能够通过软硬相协调屈服抵抗大变形,这是基于应变设计管线钢的研究热点.为探究生产工艺对双相组织形态的影响规律,利用Gleeble-3800热模拟试验机,通过压缩试验模拟轧制和冷却,研究了两阶段冷却工艺对基于应变设计X70管线钢形变奥氏体组织转变的影响.结果表明:一阶段缓冷后的待温处理使铁素体形核温度降低,有效提高了铁素体形核率,起到细化晶粒作用;降低二阶段快冷开冷温度可以增加铁素体析出时间,从而增加铁素体的含量;二阶段快冷中,提高冷却速率和降低终冷温度均可细化贝氏体组织的板条间距以及板条间的碳化物,提高了贝氏体显微维氏硬度.
关键词:
管线钢
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基于应变设计
,
热模拟
,
两阶段冷却
,
双相组织
米丰毅
,
龚雪辉
,
袁武华
,
梁剑雄
,
王长军
材料开发与应用
在Gleeble-3800热模拟试验机上对Nitronic60奥氏体不锈钢进行高温等温压缩实验,研究该材料在变形温度为950-1 200℃、应变速率为0.01-10 s-1、真应变量0.9等条件下的热变形行为,并观察了变形后的显微组织.研究结果表明:在热压缩过程中,流变应力随变形温度的升高而降低,随应变速率的升高而增加;当变形速率较低时,材料在变形温度范围内均发生了动态再结晶.采用双曲正弦模型建立了相应的热变形本构关系,其热变形激活能为425.542 kJ/mol,高温压缩变形时,Z参数和流变应力方程分别为Z=(ε)exp(425.542/RT)=3.495×1015[sinh(0.005 93σ-) 5.55,(ε)=3.495×1015[sinh(0.005 93σ)]5.55exp[-525.524/(RT)].
关键词:
奥氏体
,
不锈钢
,
热模拟
,
压缩变形
,
本构方程
潘鑫
,
李小宝
,
张宇
,
曾仰正
钢铁研究学报
工业化试制了3种厚度规格(20,26和36mm)的新型低成本高焊接性能船板钢EH36.试制钢板的显微组织由多边形铁素体和针状铁素体构成,其力学性能满足EH36级别船板要求并具有优异的低温韧性.采用焊接热模拟评价了钢板的焊接性能,当热输入由30kJ/cm升高至160kJ/cm时,粗晶区原奥氏体晶粒尺寸逐渐增大,其组织也逐渐由粒状贝氏体向晶界铁素体+晶内针状铁素体+晶内多边形铁素体转变,维氏硬度逐渐下降,低温韧性优异.得益于TiN粒子对奥氏体晶粒长大的抑制作用,微量B元素对先共析铁素体转变的抑制作用以及BN粒子对晶内铁素体形核的促进作用,焊接粗晶区获得了有利于韧性的细化组织,保证了粗晶区具有优异的低温韧性.双丝埋弧焊试验也验证了钢板具有优异的焊接性能.
关键词:
船板钢EH36
,
热模拟
,
晶内形核铁素体
,
低温韧性
,
双丝埋弧焊
刘成宝
,
翟正龙
,
窦圣朋
,
戈文英
材料热处理学报
利用热模拟实验机Gleeble 3800结合锻造实验、显微组织观察、电子探针成分分析等方法研究了加热温度、变形温度、变形量、冷却速率对齿轮钢SAE8620H连铸坯表层区域和内部区域试样的带状组织的影响,结果表明,元素偏聚小的表层区域无带状组织形成,元素偏析明显的内层区域在适宜的条件下形成不同程度的带状组织,锰等元素的偏析是带状组织形成的必要条件,可以通过提高加热温度、增大变形量等方式减轻或降低带状组织.
关键词:
带状组织
,
齿轮钢
,
热模拟
