Microstructure and Properties of Nickel-Based Gradient Coatings Prepared Using Cold Spraying Combined with Laser Cladding Methods

Sainan Liu; Yangyang Sun; Pengyuan Zhai; Pengyu Fan; Yongtong Zhang; Muyang Li; Jianxiao Fang; Ruilin Wu; Zhenyang Cai

doi:10.3390/ma16041627

Microstructure and Properties of Nickel-Based Gradient Coatings Prepared Using Cold Spraying Combined with Laser Cladding Methods

Materials (Basel). 2023 Feb 15;16(4):1627. doi: 10.3390/ma16041627.

Authors

Sainan Liu¹, Yangyang Sun¹, Pengyuan Zhai², Pengyu Fan², Yongtong Zhang³, Muyang Li⁴, Jianxiao Fang⁴, Ruilin Wu⁴, Zhenyang Cai⁴

Affiliations

¹ School of Minerals Processing and Bioengineering, Central South University, Changsha 410083, China.
² New Technology Promotion Institute of China Ordnance Industries, Beijing 100089, China.
³ Henan Jianghe Machinery Co., Ltd., Pingdingshan 467000, China.
⁴ School of Materials Science and Engineering, Central South University, Changsha 410083, China.

Abstract

A cold spray-laser cladding composite gradient coating (CLGC) was successfully formed on a Cu substrate. In comparison with traditional laser cladding gradient coatings (LGC), cold spraying the pre-set Ni-Cu alloy's intermediate transition layer not only mitigates the negative impacts due to the high reflectivity of the copper substrate but also helps to minimize the difference in the coefficients of thermal expansion (CTE) between the substrate and coating. This reduces the overall crack sensitivity and improves the cladding quality of the coating. Besides this, the uniform distribution of hard phases in CLGC, such as Ni₁₁Si₁₂ and Mo₅Si₃, greatly increases its microhardness compared to the Cu substrate, thus resulting in the value of 478.8 HV_0.5 being approximately 8 times that of the Cu substrate. The friction coefficient of CLGC is lowered compared to both the Cu substrate and LGC with respective values of 0.28, 0.54, and 0.43, and its wear rate is only one-third of the Cu substrate's. These results suggest CLGC has excellent anti-wear properties. In addition, the wear mechanism was determined from the microscopic morphology and element distribution and was found to be oxidative and abrasive. This approach combines cold spraying and laser cladding to form a nickel-based gradient coating on a Cu substrate without cracks, holes, or other faults, thus improving the wear resistance of the Cu substrate and improving its usability.

Keywords: cold spraying; laser cladding; nickel-based gradient coating; wear properties.

Grants and funding

This work was supported financially by the National Defense Basic Scientific Research Program of China under Grant No. 2020208B020, the Science and Technology Innovation Program for the High-tech Sector of Hunan Province under Grant No. 2020GK4066 and Grant No. 2022GK4027.