High-energy shot peening(HESP) and then double-stage pack boriding for H13 steel were carried out.The cross-sectional morphologies of the borided samples were observed by using SEM.The phase composition of the borided samples was investigated by XRD.The friction and wear tests at an elevated temperature were carried out for the samples borided and not borided.The experimental results showed that nano-sized surface layer of H13 steel was fabricated by HESP.The Fe2B monophase layer were detected on the samples subjected to and not subjected to HESP after double-stage pack boriding.As compared to the polished specimen after double-stage pack boriding,the borided layer thickness of HESP specimen increased by 30％,and the micro-hardness of borides of HESP specimen increased by 100 HV0.1,meanwhile the calculated diffusion activation energy of HESP specimen reduced by 33 kJ/mol in the same experimental condition.Furthermore,when compared to that of the sample without being borided,the wear rates at an elevated temperature of borided specimen subjected to and not subjected to HESP can be decreased by 41％ and 25％,respectively.Due to the high hardness at elevated temperatures and excellent oxidation resistance of borided layer,the wear resistance at elevated temperatures of H13 steel subjected to double-stage pack boriding was improved remarkably.%将高能喷丸预处理与固体渗硼相结合,对H13钢进行了两段固体渗硼处理.采用SEM观察试样渗硼层微观形貌,利用XRD对渗硼后的试样进行物相分析,并对未渗硼和两段固体渗硼的试样进行高温摩擦磨损试验.结果表明,高能喷丸使试样表层获得了纳米级晶粒,抛光态试样和高能喷丸预处理试样两段固体渗硼后均得到Fe2B单相渗硼层;相比于抛光态试样,高能喷丸预处理试样两段固体渗硼层的厚度增加约30％,表层硬度提高约100 HV0.1,扩散激活能降低了33 kJ/mol.与未渗硼试样相比,抛光态试样和高能喷丸预处理试样两段固体渗硼后高温磨损率分别降低了25％和41％,渗硼层在高温下高的硬度以及良好的抗氧化性能,显著地提高了H13钢的高温耐磨损性能.
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