Friction hydro-pillar processing (FHPP) is a novel technique that involves solid-state joining of an external plug onto a substrate by plastic deformation. A systematic investigation on material flow during FHPP is required but rarely reported. The present work reports a coupled theoretical and a three-dimensional X-ray computer tomography-based experimental study using a Ti-alloy as a tracer material to realise the material flow during FHPP of a AISI 4140 steel substrate. The cumulative results showed that the central portion of the plug deformed in a series of layer-wise shear planes. However, the plasticised material towards the outer area of the plug flowed through the clearance between the plug and the substrate with excess volume moving out as flash.

中文翻译：

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摩擦液压柱加工过程中的材料流动

摩擦水柱处理 (FHPP) 是一种新技术，涉及通过塑性变形将外部插头固态连接到基板上。需要对 FHPP 期间的物料流进行系统调查，但很少报道。目前的工作报告了基于理论和三维 X 射线计算机断层扫描的耦合实验研究，使用钛合金作为示踪材料，以实现 AISI 4140 钢基材 FHPP 过程中的材料流动。累积结果表明，塞子的中心部分在一系列层状剪切平面内变形。然而，流向塞子外部区域的塑化材料流过塞子和基板之间的间隙，多余的体积作为飞边移出。