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991.
黄惠贤 《特钢技术》2006,11(2):39-41
简要介绍了镇江电厂三期工程钢内筒钛钢复合板焊接工艺,及钛钢复合板焊接质量控制要点。  相似文献   
992.
黄华  蔡继明 《特钢技术》2006,11(4):58-62
综述国内外电炉炼钢技术发展趋势。就国内外电弧炉技术现状度发展趋势进行了讨论,总结了目前电弧炉发展的短期目标、长期目标。  相似文献   
993.
活性绢云母在聚乙烯中增强作用的研究   总被引:4,自引:0,他引:4  
利用绢云母的基本特性,对其进行超音速气流粉碎及表面化学改性,改变绢云母鳞片性质,制备出聚乙烯增强剂.研究结果有利于非金属矿物深加工、树脂基复合材料等研究.  相似文献   
994.
随着2004年12月11日起,中国家电市场全面向外资开放,国外的家电连锁巨头正虎视眈眈准备全方面的一举抢滩中国市场,使得中国的家电市场战火连天,销烟弥漫.那么作为土生土长的国内家电连锁企业是如何面对这种竞争日益激烈的市场,在有限的国内市场分得一份大的蛋糕,让自已吃得饱,吃得甜,吃得香?为此,质诚中国网的记者采访了国关电器广宣部经理周志坚,了解到国美对此的战略方向.  相似文献   
995.
The interaction between precipitation and recrystallization and its effect on the properties of the Cu-Ni-Si-Cr alloy during aging were discussed. The results show that the deformation results in much more dispersed precipitation of the phases. The precipitations have accelerating or retarding effects on the recrys allization. On the formation and growth of recrystallization, the precipitated phases are coarsed or dissolved in front of grain boundaries following a re-precipitation in the recrystallization area.  相似文献   
996.
结合广东进出口玩具检验中心获得CNAL及香港HOKLAS认可的体会,简要介绍了CNAL认可准则对检测仪器的技术要求的理解要点,探讨了如何按认可准则要求对检测仪器进行技术管理。  相似文献   
997.
用落锤冲击试验机确定隔振器冲击刚度的新方法   总被引:1,自引:4,他引:1  
落锤试验方法,因装置结构简单,操作方便,现已成为在隔振器冲击性能研究领域中重要的手段。介绍一种确定隔振器冲击刚度的新方法——波形组合法。该方法认为,尽管冲击过程中存在着“回弹”,波形成为断续的脉冲,但质量块在空中运动中能量损失很小,可以用适当的方法把它们组合成连续波形,以致我们可以用成熟的振动分析技术进行数据处理。还介绍了用函数分解法帮助提取畸变波形中冲击性能参数的方法。  相似文献   
998.
Two quanternary systems, Ir-Nb-Ni-Al and Ir-Nb-Pt-Al, were successively investigated to assess their possible use in ultra-high-temperature applications. The phase relationships concentrated on the fcc/L12 two-phase region were primarily established, and the mechanical properties were studied. Ir-Nb-Ni-Al quaternary alloys around the Ir-rich or Ni-rich corners of the Ir-Nb-Ni-Al tetrahedron showed a coherent fcc/L12 two-phase structure, analogous to that of Ni-base superalloys; however, most of the alloys presented three or four phases with two types of L12 phases. Although these alloys showed a high compressive strength at high temperature, they exhibited a higher creep rate than Ir-base binary and ternary alloys. Another quanternary system, Ir-Nb-Pt-Al, showed promising results. Only an fcc/L12 two-phase structure was found in all the alloys investigated with compositions ranging from the Ir-rich side to the Pt-rich side, and the lattice misfit between the fcc and L12 phases was small. The high-temperature strength at 1200 °C of Ir-Nb-Pt-Al alloys was higher than that of Ir-Nb-Ni-Al alloys with the same Ir content (at. pct). Moreover, Ir-Nb-Pt-Al alloys exhibited excellent creep resistance at 1400 °C and 100 MPa. This article is based on a presentation made in the symposium entitled “Beyond Nickel-Base Superalloys,” which took place March 14–18, 2004, at the TMS Spring meeting in Charlotte, NC, under the auspices of the SMD-Corrosion and Environmental Effects Committee, the SMD-High Temperature Alloys Committee, the SMD-Mechanical Behavior of Materials Committee, and the SMD-Refractory Metals Committee.  相似文献   
999.
Ir-base alloys with the fcc and L12-Ir3X (X = Nb, Zr) two-phase structure have been developed as next-generation high-temperature materials. The compressive creep behavior of Ir-Nb and Ir-Zr alloys was investigated at 2073 K under 137 MPa. The effect of addition of the third element, Zr, on the creep behavior of an Ir-Nb alloy was also investigated at 2073 K for 137 MPa. The creep rate became two orders lower by addition of a small amount of Zr. The lattice misfit change between the fcc and L12 two phase by addition of Zr and the deformation structure in binary and ternary alloys after a creep test were also investigated. The creep behavior is discussed in terms of the lattice misfit, precipitate shape, and their distribution. This article is based on a presentation made in the symposium entitled “Beyond Nickel-Base Superalloys,” which took place March 14–18, 2004, at the TMS Spring meeting in Charlotte, NC, under the auspices of the SMD-Corrosion and Environmental Effects Committee, the SMD-High Temperature Alloys Committee, the SMD-Mechanical Behavior of Materials Committee, and the SMD-Refractory Metals Committee.  相似文献   
1000.
Effects of minor additions of Cu, Bi, and In on microstructure, melting temperature, and tensile properties of Sn-Ag-based lead-free solders were investigated. It was found that the intermetallic compounds (IMCs) Ag2In and Cu6Sn5 are formed in In- and Cu-containing solders, respectively. At low concentration, Bi dissolved in the Sn matrix and tended to precipitate pure Bi particles at the solubility limit of 4 wt pct Bi. The formation of large Ag3Sn precipitates from the solder matrix was suppressed when alloying bismuth into the Sn-Ag alloy. The Bi addition resulted in a significant linear increase of the ultimate tensile strength (UTS) of solders, which is attributed to a solid-solution hardening mechanism. Solder strengthening due to In and Cu is less pronounced and attributed to a dispersion strengthening mechanism. The additions of Cu, Bi, and In all depressed the melting temperatures of Sn-Ag-based solders; however, In is the most effective one.  相似文献   
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