基于有限元仿真分析的常用石墨材料电阻率测量方法及设备设计

Resistivity Measurement of Irregularly-Shaped Graphite Heater:A Simulation and Experimental Study

石墨材料已成为真空加热设备尤其是高温(>1600℃)真空炉的首先材料,电阻率是其作为加热元件的首选指标。真空电阻炉用石墨件经过设计、加工,多为异形件,为了更好的掌握石墨材料的相关理化指标,本文利用ANSYS软件对常见的几种石墨件进行了仿真分析,并结合仿真结果给出了石墨电阻炉常用原件的测量及测量夹具的设计原则。

Herein,we addressed the resistivity measurement of the irregularly-shaped heaters,made of isostatic-pressure graphite and widely used in high temperature（ 〉1600℃） vacuum furnace. The voltage distributions in the heaters,particularly in the rectangular graphite plates with and without twin electric connection holes,were mathematically modeled,numerically simulated in finite element method with ANSYS software and experimentally evaluated. The discrepancy between the simulated and measured voltages was 0. 6% for the graphite plate without twin-hole,whereas for the graphite plate with twin-hole the largest error,near the high voltage end,was 5%. In addition,the influence of the contact area and position of the newly-designed pair of electric clamps on the accuracy of resistivity was investigated for design optimization. We suggest that the simulated results be of some technological interest in fabrication and applications of graphite heaters.