冷压成形模具钢42CrMo脉冲电压刻蚀加工表面纹理分析

Surface Texture Analysis of Cold-pressed Die Steel 42CrMo Pulsed Voltage Etching

以42CrMo钢为例,研究不同电参数电化学刻蚀对合金钢表面纹理的影响。分别采用电压值不同的直流电压、不同频率和占空比的14 V非负脉冲和14 V正反脉冲对42CrMo合金钢进行电化学刻蚀加工。使用表面轮廓仪对加工后的表面进行数据采集,并使用数值分析方法对表面的形貌进行评估。结果表明:刻蚀电压过低,导致刻蚀速率过小,刻蚀电压过高,刻蚀表面质量较差,电压为14 V时刻蚀总体效果较优。在正脉冲条件下,由于特定的电化学刻蚀系统本身存在固有频率的影响,实验采用频率为占空比50%的PWM刻蚀可得到表面粗糙度相对较低的表面,频率为1kHz、占空比为5%时,得到的表面粗糙度最高,其表面可用于增加摩擦。在正反脉冲刻蚀条件下,低占空比情况下反脉冲电镀效果抵消正脉冲刻蚀效果导致刻蚀速率缓慢,但其表面粗糙度较低,频率为20 kHz、占空比为50%时,表面粗糙度最低,该参数可用于电化学精加工。

Taking 42CrMo as an example, the effects of electrochemical etching with different electrical parameters on the surface texture of the alloy steel were studied. DC voltages with different voltage values,14V non-negative pulses and 14V positive and negative pulses with different frequencies and duty ratios were used to electrochemically etch 42CrMo alloy steel.Surface data was collected on the processed surface using a surface profilometer, and the surface topography was calculated using numerical analysis methods. The results show that the etching voltage is too low, resulting in too small etching rate, high etching voltage, resulting in poor etching surface quality. The overall effect of etching is better when the voltage is 14V. Under the condition of positive pulse etching, the etching system itself has the influence of natural frequency. The test uses PWM etching with a frequency of 20 kHz and a duty cycle of 50% to obtain a surface with relatively low surface roughness. When the frequency is 1 kHz and the duty cycle is 5%, the obtained surface roughness is the highest, and its surface can be used to increase the friction;under the condition of positive and negative pulse etching, the effect of negative pulse plating at low duty cycle offsets the effect of positive pulse etching, resulting in a slow etching rate, but its surface roughness is low, when the frequency is 20 kHz and the duty cycle is 50%, the surface roughness is lowest, and the surface can be used for electrochemical finishing.