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提出了一种采用中高频感应加热来改善渗碳过程中硬化层生长动力学的方法。对21TiMnCr12（18HGT）钢在天然气中进行了中频（2000 Hz）感应加热渗碳的试验研究，结果表明渗碳过程得到了显著加快。对由专门设计的试验方案获得的数据进行了统计处理，并在此基础上推导出了渗碳过程模型。基于菲克第二定律求解准则数，利用波波夫方法得出了这些工艺条件下的扩散系数和吸附速率常数，其数值约比在电阻炉中采用普通工艺所获得的数值高两个数量级（约10－5对10－7 cm2·s －1数量级）。根据数学模型计算出的等性能场（一种由不同的加热方式和时间参数组合获得某固定渗层深度的图表形式）证明，感应渗碳大大加快了渗碳的动力学过程。“,”Induction heating using medium or high frequency currents has been proposed as a means of achieving improved layer growth kinetics during case hardening.Experimental research on the carburising of 21TiMnCr12 (18HGT)steel in natural gas by induction heating with medium frequency currents (2000 Hz)has demonstrated significant process acceleration.A model of the carburising process has been derived by statistical processing of the experimental data from a designed experimental programme.The diffusion coefficients and the adsorption rate constants in these processing conditions were derived using the Popov methodology,based on criteria solution of Fick’s second law.The diffusion coefficient and adsorption rate constant values obtained were approximately two orders of magnitude higher than those obtained for conventional processing in resistance furnaces(~10 -5 versus~10 -7 cm2 s -1 ).The form of the iso-property fields (constant values of the total case hardened depth for different values of the heat and time process parameters)calculated from the mathematical model demonstrates the highly accelerated kinetics obtained during induction carburising.