Adhesion of tin droplets impinging on a stainless steel plate: effect of substrate temperature and roughness

✍ Scribed by Navid Z. Mehdizadeh; Sanjeev Chandra; Javad Mostaghimi

• Publisher: Institute of Physics and National Institute of Materials Science
• Year: 2003
• Tongue: English
• Weight: 859 KB
• Volume: 4
• Category: Article
• ISSN: 1468-6996
• DOI: 10.1016/s1468-6996(03)00029-9

✦ Synopsis

We photographed impact of small tin droplets on stainless steel surfaces of varying temperature and roughness. To achieve high impact velocities the test surfaces were mounted on the rim of a rotating flywheel. Substrate temperature (T s ) was varied from 120 to 220 8C and surface roughness (R a ) kept at either 0.05 or 2 mm. We kept constant the impact velocity (30 m/s) and droplet diameter (0.6 mm). To form a coating 60 droplets were deposited randomly on each stainless steel test coupon. Deposition efficiency was evaluated by dividing the mass adhering to the coupon by the mass of sixty droplets prior to impact. The maximum deposition efficiency was achieved at a substrate temperature of 160 8C. For T s , 160 8C the deposition efficiency was higher on a rough surface (R a ¼ 2 mm) than on a smooth surface (R a ¼ 0.05 mm), since splats did not adhere well to the smooth surface. For T s $ 160 8C the deposition efficiency was higher on a smooth surface (R a ¼ 0.05 mm) than on a rough surface (R a ¼ 2 mm), since splats splashed less on the smooth surface.