The Factor of Structure and Mechanical Properties in the Production of Critical Fixing Hardware 38XA

• Main Authors: G.V. Pachurin, S.M. Shevchenko, M.V. Mukhina, L.I. Kutepova, J.V. Smirnova
• Format: Article
• Language: English
• Published: University of Kragujevac 2016-09-01
• Series: Tribology in Industry
• Subjects: Rolled steel; Fasteners; Stamping; Structure; Mechanical properties
• Online Access: http://www.tribology.fink.rs/journals/2016/2016-3/11.pdf
• ISSN: 0354-8996; 2217-7965

Fixing hardware made of carbon, high-carbon, and alloyed wires is one of the widespread critical parts in mechanical engineering. The characteristics of fixtures and fasteners and their performance figures are assessed at all stages of steel-making operation, from the choice of burden stock for metal smelting to the method of preparing calibrated rolled metal parts and upsetting end products. Material used for producing long high-duty bolts must be both sufficiently strong and ductile, have homogeneous mechanical properties and chemistry, and no inner or surface defects. When manufacturing fasteners, hot-rolled metal is often plastically deformed by drafting before cold upsetting, and all unacceptable defects are removed by the expensive procedure of lathe-turning. Moreover, this technology of metal processing entails losses of up to 5.5 % in chips. This paper suggests a resource-efficient and environmentally friendlier fabrication method for calibrated rolled metal items made of steel 38XA, 9.65 mm diameter, for cold die-forging of high-duty bolts used in automotive engines, which helps spare expensive lathe-machining processes. Moreover, rolled steel produced using this technology is characterized by high resistance to plastic deformation when cold, which leads to increase n wear-resistance of tools in cold die-forging of bolts.