The annealing temperature for 440 stainless steel balls is low. When heat treated for cutting tools and bearings, the recommended hardness is HRC57-59. If deep cryogenic treatment is applied, the hardness can reach HRC60.

440 Stainless Steel BallStainless steel is a high-carbon, high-chromium martensitic stainless steel. Carbon content is 1.0%, chromium content is 17%. Applications include:

主要用于 producing bearing components designed to operate in corrosive environments and under lubrication-free, strongly oxidizing atmospheres. The 440 stainless steel balls offer excellent high-temperature dimensional stability, making them suitable for use as corrosion-resistant high-temperature bearing steel as well. Additionally, they are used in the manufacture of high-quality cutting tools, such as nozzles and bearings. The 440 stainless steel balls have a lower capacity to withstand dynamic loads.

SUS440 stainless steel balls are a martensitic stainless steel with a higher carbon content than 3Cr13 steel, resulting in greater strength and hardness. Their other properties are similar to those of 3Cr13 steel, but they have poor weldability and are generally not used as welding materials. They are used for manufacturing tools. Imported from Japan, this stainless steel is used to produce bearing components for operation in corrosive environments and under strong oxidation without lubrication. The steel also exhibits good high-temperature dimensional stability, allowing for the manufacture of corrosion-resistant high-temperature bearings and cutting tools with temperatures not exceeding 250°C.

Hardness: Annealed, ≤269HB; Quenched and tempered, ≥55HRC

Heat Treatment Specifications: 1) Annealing: cool slowly at 800-900°C; 2) Quenching: oil cool at 1000-1050°C; 3) Tempering: air cool at 200-300°C.