Powder metallurgy lubricant and preparation method thereof for stainless steel

Abstract

The invention provides a powder metallurgy lubricant and a preparation method thereof for stainless steel. The lubricant comprises the raw materials of polyethylene vinyl acetate, graphite, zinc stearate, vinyl-bis-stearamide, paraffin wax, octadecyl amine, petroleum sodium sulfonate, sodium benzoate, zinc butyl octyl phosphate, octoate tributylamine, amino silicone oil, alkyl diphenylamine and oleamide. The preparation method comprises the following steps: firstly mixing the polyethylene vinyl acetate, graphite, zinc stearate, vinyl-bis-stearamide and paraffin wax, and heating at a constant temperature to obtain a mixture I; then adding the remaining raw materials into the mixture I, cooling to the room temperature, and then grinding, crushing, and sieving to obtain the lubricant. The lubricant provided by the invention can improve the green compact strength and finish surface, greatly prolongs the service life of a mould, and improves the productivity, the yield and the quality of a powder metallurgy stainless steel product.

Description

technical field [0001] The invention belongs to the technical field of powder metallurgy material additives, and in particular relates to a powder metallurgy lubricant for stainless steel and a preparation method thereof. Background technique [0002] With the continuous development of the economy, stainless steel products are used more and more widely. As a near net shape technology, powder metallurgy stainless steel has great advantages in the production of stainless steel parts with expensive raw materials. Moreover, most of the stainless steel is austenitic stainless steel or ferritic stainless steel, which leads to high processing costs due to poor processing performance. Powder metallurgy stainless steel products can avoid or reduce the amount of machining, and have more advantages in cost. But also because stainless steel belongs to high-alloy steel, the particle hardness of stainless steel powder still has Hv180-210 due to solid solution strengthening after eliminat...

AI Technical Summary

Problems solved by technology

But these lubricants have more or less problems

Micro-powdered wax products have better volatilization performance during use, but the improvement of powder metallurgy products in terms of flow rate and compaction performance of the product is not ideal, and sometimes it will reduce the flow performance of the powder, resulting in unstable filling of the mixed powder

Zinc stearate and lithium stearate are commonly used lubricants, but due to the chemical properties of the product itself, a large amount of carbon will remain on the surface of the product after sintering, and the zinc oxide after sintering will also cause pollution to the sintering furnace, affecting the product The green strength of the

Although the imported Heganus Kenolube P11 has obvious advantages in comprehensive performance, it is only limited to the high powder filling height of some products. For large-sized products, it will still affect the release of the product, and Kenolube P11 contains metal zinc. Therefore, there will still be some carbon deposits on the surface during the sintering process, which will pollute the furnace at the same time.