Coating hot stamping steel part and preparation method thereof

The invention relates to the technical field of preparation and stamping forming manufacturing of hot stamping steel with a coating, in particular to a hot stamping steel part with a coating and a preparation method of the hot stamping steel part. The method comprises the steps that a single heat preservation step is arranged to conduct first-mode austenitizing heat treatment on a first plate, and a first austenitized plate is obtained; obtaining the ratio of the thickness of an interdiffusion layer to the thickness of a surface alloy layer in the first austenitized plate; and according to the ratio, judging whether to perform austenitizing heat treatment in different modes on the plurality of plates in a manner of increasing the number of the heat preservation steps one by one or not until the nth plate is subjected to austenitizing heat treatment in the nth mode when the n heat preservation steps are set, and the ratio of the thickness of the interdiffusion layer in the nth plate to the thickness of the sur