摘要
研究在支撑材料、工艺局限等诸多因素影响情况下的特定材料以及特定工艺参数下倾斜极限问题非常重要,为此采用金属粉末激光成形技术成形旋转薄壁金属零件的方法,在相应金属粉末材料与成形工艺参数下,进行成形金属零件时侧壁倾斜极限的研究,通过测量与计算获得倾斜极限值及其对应的层间搭接率。研究表明随着薄壁旋转半径的增加,侧壁倾斜角度也相应加大,最终超过倾斜极限,造成熔覆层塌陷现象发生。揭示出层间搭接率是产生倾斜极限和熔覆层塌陷的直接原因。通过对倾斜角度、层间搭接率与薄壁旋转半径关系进行理论分析与计算,得到成形的金属零件侧壁倾斜极限角度和极限层间搭接率的计算公式,为在设计无支撑CAD模型时侧壁最大倾斜角度提供依据。试验结果表明,利用该计算公式指导侧壁倾斜角度设计切实可行。
It is especially important of investigating the sloping limit of the specific material and the specific technological parameter in the case of various element influence such as support material, technology limitation and so on. By shaping the rotary thin-wall metal part adopting the metal powder laser shaping technique, the side wall sloping limit of metal part is studied in relevant metal powder material and shaping techno- logical parameter. The sloping limit and the corresponding interlaminar overlapping ratio are obtained by measuring and calculating. The side wall sloping angle increases with the thin-wall radius of turn increasing and the overlay excessive penetration phenomena happen with the sloping angle exceed- ing the sloping limit. The interlaminar overlapping ratio is the immediate cause of the sloping limit and overlay excessive penetration. The metal part side wall limit sloping angle and the limit intedaminar overlapping ratio formulas are obtained by theoretically analysing and calculating the relation among the sloping angle, the interlaminar overlapping ratio and the thin-wall radius of turn. The formulae provide the basis for devising the supportless CAD model maximal sloping angle. The confirmatory test indicates that the formulae are practical for devising the side-wall sloping angle.
出处
《机械工程学报》
EI
CAS
CSCD
北大核心
2007年第8期97-100,共4页
Journal of Mechanical Engineering
基金
国家高技术研究发展计划资助项目(863计划
2002AA420060)。
关键词
快速原型
金属粉末激光成形
金属零件
倾斜极限
层间搭接率
Rapid prototyping Metal powder laser shaping Metal part Slope limit Overlapping ratio between layers
