采用熔盐脉冲电解法对20钢进行渗硼实验,利用正交试验考察了电流密度、占空比、渗硼温度、时间及硼砂物质的量等因素对渗硼层厚度的影响。结果表明,各因素对20钢渗硼层厚度影响的主次顺序为,渗硼温度〉电流密度〉硼砂物质的量〉占空比〉渗硼时间。最优工艺参数电流密度为12A/dm^2、占空比20%、渗硼θ为850℃、t为90min、熔盐摩尔配比n(NaCl):n(KCl):n(NaF):n(Na2B4O7)=1:1:3:0.04。按最优工艺进行电解渗硼,得到的渗层较厚,渗层组织较细致紧密。
Boronized layer was prepared on 20 steel by molten salt electrolysis. The effects of process parameters including current density, duty cycle, boronizing temperature, boronizing time and borax amount on thickness of the boronized layer were studied through orthogonal experiments. The results showed that sequence of the five influencing factors on boronzied layer thickness was : boronizing temperature 〉 current density 〉 borax amount 〉 duty cycle 〉 boronizing time. The optimum process parameters were as follows : current density was 12 A/dm^2 ,duty cycle was 20% , boronizing time was 90min. , boronizing temperature was 850 ℃ ,molar ratio of the molten salts was NaCl: KCl: NaF: Na2B4O7 = 1: 1:3:0.04. By this optimized process, thicker boronized layer with denser microstructure was obtained.