深型腔模具精密加工技术的研究与实现

Research and realization of the precise machining technology for forging dies with deep pocket

针对淬硬工具钢切削性能差、深型腔模具加工廓形精度不易保证等问题,提出了一种深型腔模具精密高速加工工艺优化技术。该技术根据构建的加工刀轨长度以及刀具悬伸长度与型腔加工廓形误差之间的数学模型,计算随加工刀轨长度变化的廓形误差值,设计瞬时的螺旋线加工刀轨,运用曲线过渡法,生成了适合深型腔模具精密高速加工的优化刀轨。基于米克朗Duro800高速加工机床,对内星轮模具型腔进行精密加工,结果表明,加工精度可提高IT1～2级,表面粗糙度Ra≤0.8。

Aiming at the difficulty of maintaining the contour precision of forging dies with deep pocket,an optimizing technology of precise machining forging dies with deep cavity is put forward.According to measuring errors of pocketing die,a mathematical model correlation to the length of a tool-path,the available length of a cutting tool and the profile errors are characterized.After the calculation of the profile errors that vary with the length of the tool-path,the helix shaped tool-path can be created.Moreover,the optimized tool-path for machining forging dies with deep cavity is also generated by using the smooth curve as transition tool-path.Depending on the Mikron Duro 800 High-speed Machining Center,a precision cavity of forging die for shaping internal-star-wheel parts can be machined.The experimental results indicate that the profile precision has been improved by IT 1～2 and the surface roughness has also been controlled under Ra0.8 by the optimizing technology.