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Al-Al4C3细化剂和超声场对纯Mg组织的影响高声远1,乐启炽1,张志强1,崔建忠1(1.辽宁省沈阳市东北大学材料电磁过程研究教育部重点实验室)摘 要:在不同Al-Al4C3细化剂添加量条件下,对纯Mg熔体进行孕育处理.当添加质量分数为1.0%Al Al4C3细化剂时细化效果最佳,α-Mg晶粒平均尺寸由毫米级降至106μm.在纯Mg熔体中施加不同功率超声场,当施振功率为600 W时细化效果最好.研究表明,空化泡破碎产生的过冷对形核具有促进作用,空化泡的破裂及声流对熔体的搅动使得细小枝晶破碎,形成新的结晶核心,......
Absorption of sulfur dioxide using membrane and enhancement of desorption with ultrasound XUE Juan-qin(薛娟琴), LI Jing-xian(李京仙), LU Xi(卢 曦), MAO Wei-bo(毛维博), WANG Yu-jie(王玉洁), WU Ming (吴 明.... It is concluded that lower ultrasonic frequency results in a better degassing efficiency. The using of ultrasound in desorbing sulfur dioxide from citrate solution improves the desorbing efficiency......
and Environment and Tourism, Hunan University of Arts and Science, Changde 415100, China)Abstract:A finite element reconstruction algorithm for ultrasound tomography based on the Helmholtz equation... of contrast levels.Key words:ultrasound computed tomography; nondestructive testing; concrete; exact field; finite element method......
化硼 中图分类号:O627 文献标识码:A 文章编号: 1672-7207(2005)03-0448-04 Synthesis of trialkyboranes by ultrasound wave method andpreparation of boron carbide by thermal decomposition method ZHANG Hong-ping1, TANG..., tributylborane) were synthesized with the aid of ultrasound wave. The effect of ultrasound wave on yield of products was investigated and the structure and compositions of the as-prepared products were......
the end surface 15-55 mm. When the depth of vibration increases, the cavitation area was reduced. Cavitation simulation results are in good agreement with the experimental results. Key words: ultrasound...), 2012, 43(9): 54-58. [2] 李晓谦, 林森, 蒋日鹏. 超声波对 AlTiC 细化剂的活化机理研究[J]. 华中科技大学学报(自然科学版), 2013, 41(6): 11-15.LI Xiaoqian, LIN Shen, JIANG Ripeng. Effect of high intensitive ultrasound on AlTiC refiner[J......
fabricated with exothermic reaction process under high-intensity ultrasound produced by the magnetostrictive transducer were investigated. In this method, the microstructure and grain refining performance... observations show a decreasing trend in the grain size of the composites due to the ultrasound and the content of TiB2 particles in the composites. Compared with the process without ultrasound, the morphology......
Ultrasound enhanced friction stir welding of aluminum and steel:Process and properties of EN AW 6061/DC04-JointsMarco Thom?1,Guntram Wagner1,Benjamin Stra?2,Bernd Wolter21. Chair of Composites... was conducted by ultrasound enhanced friction stir welding(USE-FSW). The power ultrasound was introduced into one of the metal sheets by an ultrasonic roll seam module synchronously to the FSW......
Effect of Ultrasound on Heterogeneous Nucleation in TIG Welding of Al–Li AlloyQi-Hao Chen,San-Bao Lin,Chun-Li Yang,Cheng-Lei Fan,Hong-Liang GeState Key Laboratory of Advanced Welding and Joining,Harbin Institute of Technology摘 要:The effect of ultrasound on heterogeneous nucleation in a tungsten inert gas(TIG) weld pool of 2195 Al–Li alloy has been......
电磁搅拌对钢包精炼炉内金属液行为的影响李炎华1,苏志坚1,赫冀成1(1.辽宁省沈阳市东北大学材料电磁过程研究教育部重点实验室)摘 要:以侧壁配备电磁搅拌系统的钢包精炼炉为背景,分别利用多普勒超声波测速仪以及激光液位仪对几种电磁搅拌方式下金属液的内部流动以及表面波动状况进行了测定及分析.研究发现,电磁搅拌可以有效促进金属液的内部流动以及表面波动,从而显著改善金属液内部的动力学条件,是提高钢包精炼效率的有效手段;不同电磁搅拌方式对金属液的内部动力学条件影响的差异明显,在不同的精炼工艺要求下,可以考虑采用不同的电磁搅......
Evaluating ultrasound signals of carbon steel fatigue testing using signal analysis approachesM. M. Padzi, S. Abdullah, M. Z. Nuawi, S. M. Beden, Z.M. Nopiah(Department of Mechanical and Materials Engineering, Universiti Kebangsaan Malaysia, UKM Bangi 43600, Malaysia)Abstract:The application of ultrasound techniques to monitor the condition of structures is becoming more prominent because......