Application case overview
The traditional process is point-hard chromium plating to enhance the surface hardness of the pillars and improve wear resistance and corrosion resistance. As the country attaches great importance to environmental protection, electroplating companies reduce costs and other factors. Hydraulic prop manufacturers have adopted laser technology to replace traditional electroplating processes.
Case number one:
Laser repair name: Coal machine column
Powder material used: martensitic stainless steel
Basic situation of laser cladding parts: The total length of the test part is 1000mm, the outer diameter is 217mm, the wall thickness is 13.5mm, and the cladding length is 940mm.
Laser cladding situation
The continuous laser cladding time is 45 minutes, and the cladding surface efficiency is 0.84 square meters/hour.
Circular runout change before and after cladding <0.10mm
Straightness change before and after cladding <0.12mm
Cladding layer surface - no obvious oxidation, the coating is dense and has a metallic luster
PT flaw detection on the surface of the cladding layer - shows no cracks
Cross-sectional metallographic diagram of the cladding layer – the cladding layer is dense, metallurgically bonded to the substrate, and the dilution rate is <1%
Comparison picture before and after cladding - single layer cladding layer thickness 370±15µm, powder utilization rate: 93.7%
Case 2:
Laser repair name: Coal machine hydraulic column
Use powder material: 27SiMn
Project information: The product is a hydraulic pillar on a coal machine. The traditional process is electroplating hard chromium to enhance the surface hardness of the pillar and improve wear resistance and corrosion resistance. As the country attaches great importance to environmental protection, electroplating companies reduce costs and other factors. Hydraulic prop manufacturers have adopted laser cladding technology to replace traditional electroplating processes.
Skills requirement:
1. Hardness reaches above 500HV;
2. The cladding layer can be machine-added to a thickness greater than 0.3mm (one side);
3. The protection level after 200 hours of neutral salt spray (NSS) test is not lower than the provisions of level 9 in GB/T 10125-2012;
4. The cladding layer must not have defects such as pores, impurities, cracks, etc.
