Au-Si非晶态合金的恒温相变

用电阻测定及X射线衍射法研究了共晶成分Au-Si合金快速凝固箔带在等温时效时的相变过程,提出了由非晶态至平衡态的四阶段转变顺序,分析了各亚稳相的结构和电子浓度特征,说明在等温时效过程中亦可生成Hume-Rothery电子化合物及尺寸因素化合物。     

MICROSTRUCTURES AND MECHANICAL PROPERTIES OF RAPIDLY SOLIDIFIED Al-Fe-Cr-Zr-V-Si ALLOY AND THEIR THERMAL STABILITY

１ＩＮＴＲＯＤＵＣＴＩＯＮＴｈｅｍｅｃｈａｎｉｃａｌｐｒｏｐｅｒｔｉｅｓｏｆｔｈｅｃｏｎｖｅｎｔｉｏｎａｌａｅｒｏｎａｕｔｉｃａｌｈｉｇｈｓｔｒｅｎｇｔｈａｌｕｍｉｎｉｕｍａｌｌｏｙｓｄｅｇｅｎｅｒａｔｅｒａｐｉｄｌｙｗｈｅｎｔｈｅｔｅｍｐｅｒ...     

DEFORMATION AND FRACTURE OF DISPERSION-STRENGTHENED HIGH-TEMPERATURE AI-8.5 Fe-1.3 V-1.7 Si ALLOY

Therapidlysolidified(RS)AIFeVSialloyisoneofthemostpromisinghigh--temperaturematerialsforaerospaceapplicationsduetoitsgoodroom--andelevated--temperaturemechanicalpropertiesandexcellentthermalstability['--'J.Recently,moreandmoreattentionshavebeenpaidtothetoughnessofthisalloy.Someliteratureshavereportedtherelationshipbetweenfracturepropertyandmicrostructure[5],theembrittlenessresultingfromthehigh--temperatureexposure['jandthefatiguecrackgrowthfeature[7:inRSAIFeVSialloys,whichallmanifestthat…     

Second phases of rapidly solidified AlFeCrZrVSi alloy and their thermal stabilities

ＳＥＣＯＮＤＰＨＡＳＥＳＯＦＲＡＰＩＤＬＹＳＯＬＩＤＩＦＩＥＤＡｌＦｅＣｒＺｒＶＳｉＡＬＬＯＹＡＮＤＴＨＥＩＲＴＨＥＲＭＡＬＳＴＡＢＩＬＩＴＩＥＳＸｉａｏＹｕｄｅＬｉＳｏｎｇｒｕｉＬｉＷｅｎｘｉａｎＺｅｎｇＺｈｉｈｕａＭａＺｈｅｎｇｑｉｎｇ（Ｄｅｐａ...     

含Sc和Zr的2618铝合金冷轧板材退火时组织性能的变化

测量了含微量Ｓｃ和Ｚｒ的２６１８铝合金冷轧板材退火时的硬度变化 ,用金相显微微镜和透射电镜观察了合金的显微组织。结果发现加入Ｓｃ和Ｚｒ后,合金中生成的细小弥散的共格Ａｌ３质点可有效地钉轧位错。稳定结构,阻止晶界推移从而抑制合金退火时再结构的发生,对提高２６１８合金的耐热性能有利。     

简化物理模型的卡通火焰模拟

提出一种简化流体物理模型并实现风格化卡通火焰的方法,通过简化外力项及使用实验得出的最佳数值代替每个温度层上的浮力,避免复杂的浮力计算。通过Helmholtz-Hodge分解,分别计算对流、扩散、投影项,整个求解过程是稳定的。该方法因为减少了温度对外力的影响的计算,以及减少了旋流项的计算,速度得到了较大的提高,能高效地实现卡通风格的火焰模拟。     

Effect of Trace Sc and Zr on the Mechanical Properties and Microstructure of Al Alloy 2618

An experimental 2618(Al-Cu-Mg-Fe-Ni) alloy added with trace Sc and Zr was prepared by ingot metallurgy (IM) method. The aging behavior of the alloy was studied by Vickers hardness measurement at 200℃ and 300℃, and the tensile properties of alloy specimens were measured at 20℃, 200℃, 250℃ and 300℃. The microstructure was observed by using optical microscope, SEM and TEM. It was found that the addition of Sc and Zr to 2618 alloy resulted in a primary Al3(Sc,Zr) phase which could refine the grain because it acts as nuclei of heterogeneous crystallization in the melt during solidification. The secondary Al3(Sc, Zr) particles were full coherent with matrix and had obvious precipitation hardening effect. They also made the S' phase precipitate more homogeneous. So the strength of alloy increases at both ambient and elevated temperatures without a decrease of ductility. The ductile fracture of alloy occurs by microvoid nucleation, growth and coalescence, so the microvoid coalescence is the dominant fracture mechanism.     

含稀土镁合金的研究与开发

重点阐述了含稀土镁合金的研究,开发和应用情况,比较了稀土在铸造、变形及快速凝固镁合金中的物理化学作用,并简介了我国稀土镁合金材料的研究开发现状。     

过渡金属Fe,Ni,Sc,Zr对2618铝合金组织和性能的影响

配制了３种不同成分的Ａｌ－Ｃｕ－Ｍｇ－Ｆｅ－Ｎｉ－（Ｓｃ,Ｚｒ）实验合金,测量了合金在２００℃的时效曲线及室温,３００℃下的拉伸性能,采用金相显微镜、扫描电镜（能谱）和透射电镜观察了合金不同状态下的显微组织。结果表明：加入微量Ｓｃ和Ｚｒ后生成的一次Ａ１３（Ｓｃ,Ｚｒ）相可明显细化基体晶粒,二次析出的Ａ１３（Ｓ质点有明显的时效硬化效果,并且有利于合金中另一强化相Ｓ（Ａ１２ＣｕＭｇ）更均匀析出,从而提     

热轧变形对快凝Al—Fe—V—Si粉热挤合金断裂行为的影响

研究了不同热变形条件下用快凝Ａｌ－Ｆｅ－Ｖ－Ｓｉ合金粉挤压成形样品的拉伸断裂行为。结果表明，在沿轧制方向拉伸的试样中，与板面平行的颗粒界面处形成的微裂纹不影响主裂纹的扩展，沿与板材纵截面平行的颗粒界面的开裂可能导致试样反常断裂，沿与板材横截面平行的颗粒界面则易成为主裂纹的低能扩展路径，使试样沿颗粒断裂。