机械工程学报
機械工程學報
궤계공정학보
Journal of Mechanical Engineering
2015年
17期
177-183
,共7页
徐辉%顾琳%赵万生%洪汉%张发旺%陈吉朋
徐輝%顧琳%趙萬生%洪漢%張髮旺%陳吉朋
서휘%고림%조만생%홍한%장발왕%진길붕
高速电弧放电加工%流体动力断弧%材料去除率%工具电极相对损耗比
高速電弧放電加工%流體動力斷弧%材料去除率%工具電極相對損耗比
고속전호방전가공%류체동력단호%재료거제솔%공구전겁상대손모비
blasting erosion arc machining%hydrodynamic arc breaking mechanism%material removal rate%relative tool wear ratio
基于流体动力断弧的高速电弧放电加工(Blasting erosion Arc machining, BEAM )是一种利用高速流场控制电弧放电,高效蚀除工件材料的特种加工新技术.该技术从原理到实现都与传统的电火花放电加工(EDM)有着本质区别.将高能量密度的电弧、具有三维型面的多孔电极、极间的高速工作液流场以及多轴联动进给这四种关键要素的有效结合,实现了一种新型而高效的材料去除加工方法.采用石墨集束电极对典型的难切削材料——镍基高温合金GH4169进行了高速电弧放电加工.试验结果表明,在放电峰值电流为500 A时,最大材料去除率可达14 000 mm3/min,而最小电极相对损耗比不超过1 %,且加工后工件的表面硬度低于基体硬度,再铸层和热影响层厚度均小于100 μm,有利于切削等后续半精加工工艺的开展.由此可见,高速电弧放电加工的工艺特性使其非常适合于难切削材料的大余量去除加工.使用多孔成形电极分别对不同形状的型腔样件进行了层铣和沉入式高速电弧放电加工,证明了其高效加工三维特征零部件的能力.
基于流體動力斷弧的高速電弧放電加工(Blasting erosion Arc machining, BEAM )是一種利用高速流場控製電弧放電,高效蝕除工件材料的特種加工新技術.該技術從原理到實現都與傳統的電火花放電加工(EDM)有著本質區彆.將高能量密度的電弧、具有三維型麵的多孔電極、極間的高速工作液流場以及多軸聯動進給這四種關鍵要素的有效結閤,實現瞭一種新型而高效的材料去除加工方法.採用石墨集束電極對典型的難切削材料——鎳基高溫閤金GH4169進行瞭高速電弧放電加工.試驗結果錶明,在放電峰值電流為500 A時,最大材料去除率可達14 000 mm3/min,而最小電極相對損耗比不超過1 %,且加工後工件的錶麵硬度低于基體硬度,再鑄層和熱影響層厚度均小于100 μm,有利于切削等後續半精加工工藝的開展.由此可見,高速電弧放電加工的工藝特性使其非常適閤于難切削材料的大餘量去除加工.使用多孔成形電極分彆對不同形狀的型腔樣件進行瞭層鐉和沉入式高速電弧放電加工,證明瞭其高效加工三維特徵零部件的能力.
기우류체동력단호적고속전호방전가공(Blasting erosion Arc machining, BEAM )시일충이용고속류장공제전호방전,고효식제공건재료적특충가공신기술.해기술종원리도실현도여전통적전화화방전가공(EDM)유착본질구별.장고능량밀도적전호、구유삼유형면적다공전겁、겁간적고속공작액류장이급다축련동진급저사충관건요소적유효결합,실현료일충신형이고효적재료거제가공방법.채용석묵집속전겁대전형적난절삭재료——얼기고온합금GH4169진행료고속전호방전가공.시험결과표명,재방전봉치전류위500 A시,최대재료거제솔가체14 000 mm3/min,이최소전겁상대손모비불초과1 %,차가공후공건적표면경도저우기체경도,재주층화열영향층후도균소우100 μm,유리우절삭등후속반정가공공예적개전.유차가견,고속전호방전가공적공예특성사기비상괄합우난절삭재료적대여량거제가공.사용다공성형전겁분별대불동형상적형강양건진행료층선화침입식고속전호방전가공,증명료기고효가공삼유특정령부건적능력.
A novel high-efficiency arc discharge machining process named blasting erosion arc machining (BEAM) based on hydrodynamic arc-breaking mechanism is proposed and implemented. It substantially differs from electrical discharge machining (EDM). This technology composes of several key elements, such as high density energy input carried by arcing, multi-hole electrode with three-dimensional contour, high velocity flow field in the discharge gap, and multi-axis feed control. The BEAM is capable of machining 3D complex part with high material removal rate. The machining experiments are conducted with graphite bundled electrode as a tool, and typical difficult-to-cut material GH4169 (similar to Inconel718) as a workpiece. The maximum material removal rate (MRR) reaches 14 000 mm3/min, and the minimum relative tool wear ratio (TWR) is less than 1 % while the peak discharge current is 500 A. Meanwhile, the hardness of machined surface is lower than that of matrix and the thickness of heat affected zone and recast layer are less than 100μm. These imply that the subsequent semi-finishing process such as cutting could be applied easily. Therefore, the machining characteristics of BEAM demonstrate that it is a promising technology to deal with bulk removal roughing of difficult-to-cut materials.