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本文叙述了我国铁合金工业概况和发展速度以及“八五”期间铁合金供需预测和新厂建设问题,并对“八五”期间我国铁合金工业发展中的问题提出了看法。 相似文献
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铁合金学科发展动态分析与展望 总被引:3,自引:0,他引:3
综合阐述了近年来我国铁合金行业在生产技术、装备技术、品种质量以及节能环保方面所开展的工作,指出今后铁合金行业发展定位应以大型化核心技术,产品的“纯净化”、“精品化”、“特色化”以及生产技术创新作为长期发展任务。 相似文献
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铁合金质量品种优化的技术方向 总被引:1,自引:1,他引:0
从我中钢铁产品结构调整、冶炼工艺技术及装备改进和钢材实物质量水平提高等方面分析我国铁合金市场所面临的挑战,提出“纯净化”、“精品化”、“特色化”是我国铁合金产品质量、品种改进的重要技术方向。 相似文献
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铁合金质量、品种优化的技术方向 总被引:1,自引:0,他引:1
从我国钢铁产品结构调整、冶炼工艺技术及装备改进和钢材实物质量水平提高等方面分析了我国铁合金市场所面临的挑战,提出“纯净化”、“精品化”、“特色化”是我国铁合金产品质量、品种改进的重要技术方向。 相似文献
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Richard Fonda Anthony Reynolds C. R. Feng Keith Knipling David Rowenhorst 《Metallurgical and Materials Transactions A》2013,44(1):337-344
Friction stir welding generates periodic features within the weld. These ??onion ring?? features are associated with variations in both texture and the orientation of that texture along the length of the weld. Analysis of an AA2195 friction stir weld reveals the presence of periodic oscillations between the dominant B and $ \overline{\text{B}} $ components of the ideal shear texture, suggesting a periodic reversal in the predominant shear orientation during welding that is inconsistent with current understandings of the friction stir welding process. Microstructural features present in the weld and machine force variations during welding indicate that these textures may arise from the oscillation of an off-centered tool. Such a tool oscillation can generate a periodic extrusion of material around the tool, giving rise to the observed flow features, machine force variations, and reversals of the local shear texture orientations. A new model of material flow during friction stir welding is proposed to explain the observed features. 相似文献
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本文以飞块座部件焊接为例阐述了铁基粉末冶金用凸焊法焊接的可行性,对各焊接规范参数与焊接强度的关系作了全面的分析,对焊接中相关问题作了说明,如预制焊点的制备、焊接结构的选择、被焊材料含碳量的选择、被焊材料的密度、被焊材料的清洁度、焊接工装的设计、焊接精度的保证等,在此基础上肯定了铁基粉末冶金是可以焊接的并能够获得较高的强度和精度。 相似文献
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针对炉卷长期在高温下运行所产生的严重热裂纹,从分析母材的可焊性及焊接材料方面入手,寻找出了适合解决炉卷热裂纹的焊接技术和焊接材料,达到了焊接省时、省力且消耗低的目的。 相似文献
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采用等离子弧焊将两张3.5 mm厚纯钛板对焊,然后在1 780 mm冷轧机上依次进行变形量为43%、50%的冷轧加工,且冷轧后均进行退火处理。对两个轧程的冷轧态及退火态焊缝试样进行了金相显微组织观察;对两个轧程退火态试样进行了室温力学性能及硬度测试;对退火态成品母材区和焊缝加工区进行了杯突试验和在3.5%NaCl水溶液中的阳极极化试验。结果表明,两次冷变形板材退火后焊缝加工区晶粒尺寸均比母材区略微细小,强塑性略好一些,维氏显微硬度也稍高一些;成品板材焊缝加工区的延伸率与母材相差不大,杯突值相近,具有与母材相当的工艺性能;成品板材焊缝加工区的阳极极化行为与母材无明显差异,二者在3.5%NaCl水溶液中的耐腐蚀性基本一致。 相似文献
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介绍了Inconel 600合金材料特性、焊接性分析、焊接工艺以及检验等方面内容.通过焊接试验研究和生产实践,该工艺已成功地应用于氧化反应器的生产. 相似文献
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Gnofam Jacques Tchein Dimitri Jacquin Dominique Coupard Eric Lacoste Franck Girot Mata 《Metallurgical and Materials Transactions A》2018,49(6):2113-2123
This paper is focused on the genesis of microstructures in friction stir welding (FSW) of the Ti-6Al-4V alloy. Several titanium joints, initially prepared with four different preheat treatments, were processed by FSW. Detailed microstructural analyses were performed in order to investigate change in the microstructure during the process. In this work, the FSW processing allows a controlled and stable microstructure to be produced in the stirring zone, regardless of the initial heat treatment or the welding conditions. The welded material undergoes a severe thermomechanical treatment which can be divided into two steps. First, the friction in the shoulder and the plastic strain give rise to the necessary conditions to allow a continuous dynamic recrystallization of the β phase. This operation produces a fine and equiaxed β grain structure. Second, once the pin has moved away, the temperature decreases, and the material undergoes a heat treatment equivalent to air quenching. The material thus exhibits a β → β + α transformation with germination of a fine intergranular Widmanstätten phase within the ex-fully-recrystallized-β grains. 相似文献
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介绍了铝电解轨道接头压馈的情况及产生的主要原因,通过对其材料的技术性能,钢的焊接性能的分析,确定了运用手工焊的方案和焊接材料的选择以及焊接施工的工艺。通过实践证明了该技术的可行性。 相似文献
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N. F. Kazakov 《Powder Metallurgy and Metal Ceramics》1964,2(4):337-340
Conclusions It has been established that with diffusion welding in a vacuum and under optimal conditions, a physical interface is completely absent between the welded materials, i.e., the structure of the welding zone does not differ from the structure of the starting molybdenum disilicide. The porosity is 2.1%. The size of the pores varies from 2 to 70, and the zone of the welded bond of molybdenum disilicide is equal in strength to the base material.Tests under industrial conditions showed that the molybdenum disilicide heater, welded by diffusion welding in a vacuum, worked on a par with those imported, and lasted 3000 h at a temperature of 1650–1700°C.As a result of developing and introducing the new technology of producing molybdenum disilicide heating rods, the Moscow Hard Alloys Combine has obtained a great economic saving, of the order of 350,000 rubles in 1961–1962. 相似文献
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采用Gleeble热模拟的方法, 通过模拟焊接过程中快速加热和冷却的热循环过程, 得到1150~1300 ℃不同峰值温度下22Cr15Ni3.5CuNbN奥氏体钢扩大的热影响区组织, 并对其进行冲击性能分析. 对热影响区组织的研究表明, 实验钢的母材中存在一定量富Nb复合碳氮化物, 有效钉扎晶界, 且与大量位错缠结. 在焊接过程中, 该富Nb复合碳氮化物经历溶解与重新析出的复杂过程: 当峰值温度为1150 ℃时, 仅小颗粒的富Nb碳氮化物发生了溶解, 而峰值温度为1300 ℃时, 富Nb复合碳氮化物经历溶解与重新析出, 呈现网状的组织形貌, 且其整体尺寸增加. 富Nb复合碳氮化物的演化导致了冲击功的变化, 经历焊接热循环条件的实验钢较母材具有更高的冲击韧性, 随着峰值温度的升高, 冲击韧性呈现先升后降的趋势, 其中在峰值温度为1150 ℃时实验钢的冲击韧性最高. 相似文献
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分析奥氏体不锈钢压力容器在焊接过程中所产生的裂纹性质、形成机理,以及材料的化学成分和工艺措施对裂纹产生的影响,指出产生热裂纹的主要原因;采取了控制材料的化学成分和合理的焊接工艺等措施,以防止热裂纹的产生。 相似文献