On the Prediction of Strength from Hardness for Copper Alloys

Abstract

Hardness and strength values of over 55 copper alloys strengthened by solid solution strengthening, precipitation hardening, cold working, and dispersion strengthening were compiled. The yield strength (YS) and ultimate tensile strength (UTS) values of the copper alloys examined ranged between 50 to 1300 MPa and 200 to 1400 MPa, respectively. The compiled values were classified based on strain-hardening potential an indirect method to understand the effect of strain-hardening characteristics. Least squares regression analysis was employed to establish correlations between strength and Vickers hardness values. Strain-hardening potential showed a significant effect on the correlations. In all the cases, a linear relation was obtained for both YS and UTS with hardness for the entire range of values under analysis. Simple empirical equations were proposed to estimate the strength using bulk hardness. The proposed correlations obtained for the entire range of values were verified with experimental values. A good agreement was observed between experimental and predicted values.

Stiprių magnetinių laukų sistemoms taikomų mikrokompozitinių vario ir niobio laidininkų suvirinamumo ir suvirintųjų jungčių tyrimai

“…Gryno Cu stiprumas atkaitintoje būsenoje yra apie 220 MPa (Martienssen et al 2006) ir kinta atsižvelgiant į grūdų dydį. Didžiausią vario lydinių stiprį galima pakankamai tiksliai numatyti pagal Vikerso kietumą, naudojant paprastą tiesinę priklausomybę R m = 3,353 HV (Krishna et al 2013). Išmatuotas termitinės suvirinimo jungties metalo kietumas nuo 91 iki 96 HV.…”

Experimental and numerical assessment of subsurface plastic deformation induced by OFHC copper machining

“…Concerning the limit shear stress (t limit ), this is equal to the yield shear stress ðt y ¼ s y = ffiffiffi 3 p Þ and was calculated based on the estimated yield stress (s y ) of the deformed superficial layers of the chip and machined surface. This estimation was based on the relation between the Vickers hardness (HV) and the yield stress (s y ), which was proposed by Krishna et al [11] and given by the following equation:…”

Effect of high-pressure torsion on the microstructure and strengthening mechanisms of hot-consolidated Cu–CNT nanocomposite

“…The yield strength in Cu-based alloys can be correlated with the measured hardness values using the YS¼ 2.874 Â Hv approximation, where YS is yield strength in MPa, and Hv is Vickers hardness number [25]. Therefore, the yield strength of the nanocomposite is determined by this approximation, using the measured hardness value.…”