Use of liquid lubricant for backward extrusion of cup with internal splines using pulsating motion
Use of liquid lubricant for backward extrusion of cup with internal splines using pulsating motion
复制标题
使用液体润滑剂通过脉动运动向后挤压带内花键的外圈
DOI：
10.1016/j.jmatprotec.2017.02.001
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发表时间：
2017
影响因子：
6.3
通讯作者：
M. Sugawara
中科院分区：
文献类型：
--
作者：
T. Maeno;K. Mori;Y. Ichikawa;M. Sugawara
为了在没有磷酸盐转化涂层的情况下将液体润滑剂用于导致严重变形的冷锻和挤压操作，增强了使用伺服压力机的脉动运动的自动再润滑。在带内花键杯形件的反挤压过程中，由于冲头的脉动运动，在凸模底部产生了向杯形件内表面提供润滑剂的负压。由于在挤压过程中冲头凹槽没有完全填充金属，因此在凹槽中形成间隙，因此液体润滑剂通过这些间隙供应到冲头底部，而不会完全将冲头从杯中取出。通过脉动挤压实验，研究了冲头上冲后的保持时间、润滑剂的粘度和循环次数等因素对防咬死效果和杯形件表面质量的影响。为了缩短成形时间，采用了凸模底部和坯料顶部的润滑油腔以及增加凸模上行程的方法。
To use liquid lubricants for cold forging and extrusion operations causing severe deformation without phosphate-conversion coatings, automatic re-lubricating using pulsating motion of a servo press was enhanced. In backward extrusion of a cup with internal splines, negative pressure for supplying the lubricant to the inner surface of the cup was generated under the punch bottom by the pulsating motion. Since the punch grooves are not fully filled with metal during extrusion, the gaps are formed in the grooves, and thus the liquid lubricant is supplied through these gaps up to the punch bottom without completely taking the punch from the cup. The effects of the holding time after each punch upstroke, the viscosity of the lubricant and the number of cycles on the seizure prevention and the surface quality of the formed cup were examined from experiments of extrusion with pulsating motion. To shorten the forming time, lubricant pockets on a punch bottom and billet top and increase in punch upstroke were employed.