▎ 摘　　要

NOVELTY - An erosion-resistant graphene composite gradient coating on surface of measurement while drilling instrument outer cylinder comprises bottom layer, transition layer divided into three layers and working layer. USE - Erosion-resistant graphene composite gradient coating on surface of measurement while drilling instrument outer cylinder. ADVANTAGE - The coating structure has elemental composition with gradient changes and has performance changing gradually. The internal stress between the coating and the outer cylinder of the instrument is reduced, and the erosion resistance of the coating is improved. The binding strength of the primer layer of the coating and instrument outer cylinder is improved. The multi-layer graphene sheets added to the gradient coating material, improves the strength, hardness and erosion resistance of the coating. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for preparation of the coating.