J Mater Sci Technol ›› 2009, Vol. 25 ›› Issue (05): 577-582.

• Articles •     Next Articles

Effect of Porosity on the Mechanical Properties and WearPerformance of 2% Copper Reinforced Sintered Steel Used in Shock Absorber Piston Production

Bekir Yalcin   

  1. S.Demirel University
  • Received:2009-05-25 Revised:2009-07-20 Online:2009-09-28 Published:2009-10-10
  • Contact: Bekir Yalcin

Abstract:

Powder metallurgy (P/M) method has mainly been used to produce automobile parts such as self-lubrication beds, shock absorber parts, and gear wheels. In order to investigate the effect of porosity on the mechanical and tribological properties in sintered steel, specimens with 10%, 15%, and 20% porosity were produced in a 10 mm×10 mm×55 mm prismatic shape by pre-alloying powders of the MPIF Fe-C-0.205 alloy used in the production of shock absorber pistons. Sintering was carried out at 900°C for 45 min in an argon atmosphere. Tensile, charpy, and microhardness tests were performed on these specimens. In addition, the wear performance of a 2% Cu reinforced sintered steel alloy under dry sliding conditions was determined. Metallographic studies such as pore formation, worn surface, and fractured surface analyses were performed by scanning electron microscopy and optical microscopy. The results indicate that irregular pore formation tendencies increase with an increase in porosity (%). Furthermore, an increase in porosity was shown to decrease the mechanical properties and increase the wear trace area and the friction coefficient of sintered steel.

Key words: Shock absorber piston, Powder metallurgy, Porosity, Friction coefficient