半不连续切屑形成过程切削力动态数学模型

A Dynamic Mathematical Model for the Cutting Force in Chip Segmentation

本文在钛合金切屑形成过程动态研究的基础上,建立了能反映半不连续切屑变形规律和影响因素的动态切削力数学模型,并对钛金合切削力特性进行了实验研究,提出了控制切削用量和刀具几何参数是抑制切削振动、提高已加工表面质量、减小切削力的有效途径。

In cutting difficult-to-machine materials such as titanium alloy, stainless steel and superalloy, segmental chip appears. Much experimental work done on the observation of the process of chip segmentation and on the measurement of the periodical fluctuation of the cutting force, which affects the quality of finished surface and tool life, has been reported . Unfortunately, no mathematical description of the process of chip segmentation and no calculation formula for the periodic ally fluctuating force are available. Up to now,only formulas for static cutting force for flow type chip are available. Based on a previous paper by the authors, the present paper describes mathematically the process of the chip segmentation; and with suitable mathematical treatment, a dynamic cutting force formula for chip segmentation is obtained as follows: F_2(t)=α_(10)·α_0·τ_8{1/2[α((τ_8+τ_(min))/τ_8)+((σ_0-σ_N)/τ_8)]+1/2α·((τ_8-τ_(min))/τ_s)cos(2πt/T)} The authors believe that, using the above formula, we may succeed in controlling the chatter vibration in cutting and improving the quality of the finished surface.