A general solution is given for the removal of a surface layer either by a sharp tool or by a peeling force. The creation of the separated layer is treated as a fracture process and analysed using an energy approach. For the cutting case frictional work at the tool-layer interface is included. Elastic cutting is first analysed and then that involving plastic bending which results in the layer curling. The transition from elastic to elastic-plastic bending occurs when fracsy2h2EGc{frac{sigma_{y}^{2}h}{2EG_{c}}} . For small values of this parameter and high cutting angles there is a further transition to plastic shearing in the layer which leads to lower cutting forces. It is shown that both in this, and in some bending cases, there can be touching of the tool at the fracture which changes the nature of the process. The peeling case is shown to be a special, zero friction, version of cutting in which both elastic and elastic-plastic bending can occur. However plastic shearing is shown not to occur as it is energetically less favourable. Some comments on crack veering in high thickness cuts from mode II effects are made. Such deviations in direction can lead to none steady propagation.
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机译：给出了通过锋利的工具或通过剥离力去除表面层的一般解决方案。分离层的创建被视为断裂过程，并使用能量方法进行了分析。对于切割情况，包括在工具层界面上的摩擦功。首先要分析弹性切割，然后再进行涉及塑性弯曲的弯曲，这会导致层卷曲。当fracs y 2 h2EG c {frac {sigma_ {y} ^ {2} h}时，发生从弹性弯曲到弹塑性弯曲的过渡{2EG_ {c}}}。对于该参数的较小值和高切削角，层中会进一步过渡到塑性剪切，从而导致切削力降低。结果表明，在这种情况下以及在某些弯曲情况下，工具在断裂处都会发生接触，从而改变了过程的性质。剥皮情况显示为特殊的零摩擦切割形式，在该形式中会同时发生弹性弯曲和弹塑性弯曲。然而，显示出不会发生塑性剪切，因为它在能量上不利。对于模式II效应造成的高厚度切口中的裂缝转向提出了一些意见。这种方向上的偏差不会导致稳定传播。
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