放电诱导可控烧蚀及电火花修整成形加工基础研究

提出一种新加工方法——放电诱导可控烧蚀及电火花修整成形加工(简称间歇烧蚀加工)。利用极间金属材料在高压氧气间歇通入阶段产生剧烈烧蚀并将蚀除产物吹离加工区域这一特性来实现材料的高效蚀除及较低电极相对损耗率的目的,且在氧气关闭阶段进行常规电火花加工以对表面进行修整,保证了加工表面精度及质量。与火花油、水中传统加工和持续烧蚀加工的试验对比表明:在相同电参数下,间歇烧蚀加工的材料去除率较传统火花油中的电火花加工提高了4.28倍,相对电极损耗率降低了72%。通过放电波形分析了间歇烧蚀的加工机理,并基于电极对的表面微观形貌和成分分析对其加工特点进行了研究。     

水包油型乳化液钛合金TC4电火花加工特性研究

为解决钛合金在煤油介质中电火花加工效率低及在蒸馏水介质中加工表面质量差的问题,提出利用乳化剂将煤油和蒸馏水超声振动后形成水包油型乳化液作为工作介质的加工方法。分别以煤油、水包油型乳化液和蒸馏水为工作介质,对钛合金TC4进行放电加工试验,从加工效率、电极相对损耗率和表面质量三个方面,对比研究了不同工作介质中钛合金电火花加工的特性。试验结果表明：水包油型乳化液中的加工效率是煤油中加工效率的两倍左右,工件表面粗糙度值Ra比蒸馏水中的Ra值减小了15%~20%,加工后工件表面微裂纹较少,表面较平整,但其电极相对损耗率高。     

阶梯孔数控电解镗孔加工的阴极设计及试验研究

NC electrochemical boring method was adopted to solve the processing problems of stepped inner holes with small inlet,large inner cavity,and large deep diameter ratio.According to the structural characteristics of stepped holes,cathodes with different spiral outlets,different rotating angles,and different taper of shunt blocks were designed.The flow fields were analyzed by FLUENT,and the results show that the cathodes with 24° conical angle,360° rotating angle,and double spiral outlets meet the design requirements.Orthogonal tests were carried out to study the influences of processing parameters on removal amount and processing clearance.Main size of the cathode is determined by the testing results,and the problems of uneven wall thickness of the stepped hole are solved by correcting the tapers of the cathodes.By the proposed method,errors of the stepped hole are small,and quality of processing surfaces is good,which meet the production requirements.     

制鞋职业教育教学实训课程浅析

高职院校技能实训课程的开设是职业教育发展的需要,实训教师正确指导是学生掌握专业知识技能胜任该工作的关键。本文通过在鞋类设计教学实训课程中积累的经验,根据实训过程中存在的问题,对上好实训课提出一管之见,以供学界同仁参考。