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1.
Wang Weibin Shi Yaowu Sha Peng Lei Yongping Tian Zhiling 《Journal of Materials Engineering and Performance》2003,12(5):581-583
A 400 MPa ultra-fine grain steel possesses high strength and toughness. Due to its fine grain size, the heat affect zone (HAZ)
of the weld joint will soften during welding. The weldability of 400 MPa ultra-fine reinforced steel bar of flash butt welding
is investigated by using the micro metallographical examination and macro-mechanical-property tests. The joint of flash butt
welding has a superior mechanical property. The HAZ in the weld joint does not show apparent softening. There is only a localized
softening spot inside the weld seam, which does not affect the property of the whole joint. Therefore, flash butt welding
is appropriate for joining the 400 MPa ultra-fine grain reinforced steel bars. The resulting weld joint has excellent mechanical
properties. 相似文献
2.
0 IntroductionSelf-shielded flux cored wire is a newly developedwelding material used without gas protection. Use of suchcored wires has grown rapidly in developed countriesbecause of the following advantages: simple use, goodwind resistance ability, lower cost resulted from highproductivity and strong desulfurization ability[1]. Self-shielded flux cored wires are preferred for on-site weldingsuch as ship and barge building, storage tank, bridge,offshore oil platform buildings and so on[2 -3].… 相似文献
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2006年12月18日,中国橡胶工业协会材料研究检测中心通过国家实验室认可答谢仪式在北京举行,来自中国合格评定国家认可委员会、国家科学技术部、燕山石化、贝卡尔特、上海圣奥、江苏兴达、骏马化纤等67个单位、130名嘉宾到会表示了祝贺。会议同时对“中心”创建作出重大贡献的单 相似文献
5.
为在橡胶行业进一步实施循环经济,不断推进中国橡胶工业科学发展,不断推动废旧橡胶循环利用的科技创新,中国橡胶工业协会最近与中国石油和化学工业协会、中国环境保护产业协会在北京联合举办了“全国废旧橡胶循环利用科技创新论坛”。中国橡胶工业协会鞠洪振会长、范仁德秘书长,中国石油和化学工业协会李勇武会长、谭竹洲名誉会长、杨伟才副会长,中国环保产业协会企业部齐晓君主任出席了会议。来自中国橡胶工业协会废橡胶综合利用分会、轮胎分会、技术经济委员会、助剂专业委员会和营销工作专业委员会的相关企业和专家、各分会(专业委员会)… 相似文献
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Intensification of low-grade methane enrichment in nitrogen mixture by CH4/CO2 displacement
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To solve the problem of CO2 uncompleted desorption in the process of CO2 displacement enhancing the adsorption separation of CH4/N2, a small amount of product gas CH4 was used as purge gas to improve the CO2 desorption. CH4/CO2 mixture gas obtained from desorption step was recycled as the displacement gas to enhance the enrichment of low-grade methane in nitrogen mixture. In this work, the research conducted the experiments for CH4/N2 separation using CH4/CO2 displacement intensification adsorption and the laboratory-made coconut shell activated carbon as sorbent. The mathematical models were built in gPROMS and the accuracy of models was verified by comparison of simulations and CH4/N2/CO2 breakthrough experiments. The performance of enrichment of low-grade methane with displacement intensification using different displacer was compared. The result showed that the process with CH4/CO2 displacement had higher purity product than CO2 displacement. The CH4/ CO2 mixed gas replacement enhanced vacuum pressure swing adsorption cycle experiment was carried out, which can jointly enrich 14% CH4/ N2 and 53% CH4/CO2 to 98.8%, and at the same time obtain a recovery rate of 77.8%. 相似文献
8.
简要介绍了螺旋焊管超声波探伤中,探头自动跟踪方式的发展情况和各个跟踪方式的工作原理、系统构成及其存在的缺点。 相似文献
9.
The microstructure and hardness of the HAZ in a 800 MPa grade ultra-low-carbon microalloyed steel were studied.The results indicate that the heat affected zone (HAZ) of the RPC (Relaxation- Precipitation- Controlling) steel possesses a continuous gradient structure, and can be classified into three zones, i. e. CGHAZ ( coarse-grain HAZ ) , FGHAZ (fine-grain HAZ ) and ICHAZ ( intercritical temperature HAZ ). The microstructures in the HAZ are all composed of bainite-like structure.The microstructare in the CGHAZ mainly consists of lath-like bainite and granular bainite . The influences of heat input and t8/5 on the hardness in the HAZ of RPC steel are notable. With the increase of heat input and t8/5, the softening tendency of HAZ becomes obvious. The hardening phenomenon that normally occurs in the CGHAZ does not take place with this steel in the range of experimental conditions. The softening in the ICHAZ is bound to occur. Hence appropriate welding technologies need to be selected. 相似文献
10.