共查询到20条相似文献,搜索用时 62 毫秒
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桥梁箱型结构打底焊缝的焊接主要采用气体保护焊,要求焊接接头必须具有优良的力学性能和时效性能。采用武钢研制的WER70N气保焊丝对两种状态的WNQ570桥梁钢进行气保焊试验。结果表明:接头具有优良的弯曲和拉伸性能;接头焊缝、熔合线及热影响区-40℃冲击功最低可达71 J,韧性-脆性转变温度都在-40℃以下,具有优良的冲击韧性和时效性能;焊缝表层与中心均未出现明显的硬化和软化现象;满足桥梁钢的焊接技术要求。接头的焊缝组织均为细小的先共析铁素体和针状铁素体,过热区组织均为贝氏体。 相似文献
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通过对大厚度低合金珠光体耐热钢15CrMoR母材性能及焊接性能进行分析、试验,制订了15CrMoR钢高温压力容器的焊接工艺方案。封头对接采用气保焊,选用H08CrMnS iMoA 1.2 mm焊丝,80%Ar+20%CO2混合气体。筒体对接焊采用气保焊打底,埋弧焊填充。埋弧焊选用H08CrMoA 4.0 mm焊丝,SJ101焊剂。焊后进行消应处理。 相似文献
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固溶处理对双相不锈钢FCAW焊接接头性能的影响 总被引:1,自引:0,他引:1
采用自行研制的双相不锈钢药芯焊丝GDQA2205焊接双相不锈钢2205,焊接过程中采用ゅ(CO2)100%气体作为保护气.在保证药芯焊丝气保焊(FCAW)焊接接头性能的前提下,考察焊后1050℃固溶处理时双相不锈钢FCAW焊接接头性能的影响.具体分析了固溶处理后焊接接头各项性能的变化,发现焊缝熔敷金属的拉伸强度、焊接接头的洛氏硬度和弯曲强度等性能指标在固溶处理前后变化不大,而焊接接头的冲击韧性和焊缝熔敷金属的耐腐蚀性能在固溶处理后都有较大幅度的提高,可见焊后固溶处理对双相不锈钢FCAW焊接接头有一定实用价值. 相似文献
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用插销试验法研究了实心焊丝CO2气保焊根焊条件下X80管线钢的冷裂纹敏感性及断口特征.结果表明,预热100℃条件下X80钢的抗冷裂性好,临界断裂应力σcr为624 MPa,与其抗拉强度相当.当拘束拉伸应力高于抗拉强度时,将发生失效断裂,断裂性质为延性断裂断口.CO2气保焊进行根焊焊接时,X80钢的抗冷裂性好,与该方法能得到超低氢的焊接条件有关,此外还与该钢的裂纹敏感系数(0.17%)不高,HAZ淬硬不明显有关.焊接接头过热区的组织主要为块状铁素体,最高硬度297 HV. 相似文献
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A. A. Babakov 《Metal Science and Heat Treatment》1967,9(10):764-770
Conclusions Highly alloyed steels and alloys are produced in conformity with GOST or technical specifications in thick and thin sheets, beams and channels, bars, hot-rolled and cold-rolled pipe, and rod. Castings are produced in the specialized plant of the Ministry of Chemical and Petroleum Machine Building.The technology of welding stainless steels and alloys is given in [15] and [16].TsNIIChERMET. Translated from Metallovedenie i Termicheskaya Obrabotka Metallov, No. 10, pp. 43–50, October, 1967. 相似文献
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模具渗硼工艺及其发展应用 总被引:4,自引:0,他引:4
渗硼是提高模具使用寿命的重要途径,是在金属表面形成高硬度的金属硼化层,显著提高其耐磨性,且具有良好的耐热性和耐蚀性。近年来,随着渗硼工艺逐步改进和完善,已发展了复合渗、多元共渗及低温渗硼工艺,取得了良好的经济效果。 相似文献
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《稀有金属材料与工程》2006,23(4):23-26
结合近年来现场试验与施工实践,分析研究了中小型镍材(工业纯镍)设备与管道的特点、性能、焊接缺陷与产生原因,以及防止与消除其缺陷、优化制造施焊质量的工艺措施,并总结了若干条注意事项。 相似文献
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A. Yu. Tsivadze G. V. Ionova V. K. Mikhalko 《Protection of Metals and Physical Chemistry of Surfaces》2010,46(2):149-169
The possibility of using unique properties of lanthanides in the nanotechnology is demonstrated. The origination of linear
and nonlinear optical properties of lanthanide compounds with phthalocyanines, porphyrins, naphthalocyanines, and their analogs
in solutions and condensed state and the prospects of obtaining novel materials on their basis are discussed. Based on the
electronic structure and properties of lanthanides and their compounds, namely, optical and magnetic characteristics, electronic
and ionic conductivity, and fluctuating valence, molecular engines are classified. High-speed storage engines or memory storage
engines; photoconversion molecular engines based on Ln(II) and Ln(III); electrochemical molecular engines involving silicate
and phosphate glasses; molecular engines whose operation is based on insulatorsemiconductor, semiconductor-metal, and metal-superconductor
types of conductivity phase transitions; solid electrolyte molecular engines; and miniaturized molecular engines for medical
analysis are distinguished. It is shown that thermodynamically stable nanoparticles of Ln
x
M
y
composition can be formed by d elements of the second halves of the series, i.e., those arranged after M = Mn, Tc, and Re.
Prospects of using lanthanide superconductors in nanotechnology are considered. 相似文献