Effect of silver addition on the creep parameters of Sn-7 wt.% Bi alloy during transformation

Journal Article · Tue Jan 15 00:00:00 EST 2008 · Materials Characterization

DOI:https://doi.org/10.1016/j.matchar.2006.10.006· OSTI ID:21062177

Abd El-Salam, F ^[1]; Nada, R H; Fawzy, A ^[1]

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1. Physics Department, Faculty of Education, Ain Shams University, Cairo (Egypt)

The strain-time relations of Sn-7 wt.% Bi and Sn-7 wt.% Bi-1 wt.% Ag alloys have been obtained under different constant stresses (8.7-19.1 MPa) in the temperature range (313-373 K). The results showed that the transient and the steady state creep parameters n, {beta} and {epsilon}{sub st} depend on both the deformation temperature and the applied stress. The temperature dependence of these parameters indicates a transition temperature at 343 K. The Ag-free samples are more hard than those with Ag addition. This is explained by precipitation of Bi atoms which segregate to form a non-coherent cubic {alpha}-phase Sn-7 wt.% Bi samples. While, Ag addition prevents precipitation segregate on the grain boundaries. The analysis of the X-ray diffraction patterns shows that, Ag addition increases the Sn crystallite size but decreases Bi crystallite size. The energy activating the steady state creep in the two alloys in the low and high temperature ranges (before and after transformation temperature) were found to be 51.2 {+-} 1.6 and 88.1 {+-} 1.4 kJ/mol for Sn-7 wt.% Bi alloy and 34.3 {+-} 1.9 and 57 {+-} 1.8 kJ/mol for Sn-7 wt.% Bi-1 wt.% Ag alloy, respectively.

• OSTI ID: 21062177
• Journal Information: Materials Characterization, Vol. 59, Issue 1; Other Information: DOI: 10.1016/j.matchar.2006.10.006; PII: S1044-5803(06)00284-1; Copyright (c) 2006 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved; Country of input: International Atomic Energy Agency (IAEA); ISSN 1044-5803
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
BISMUTH ALLOYS
CREEP
DEFORMATION
GRAIN BOUNDARIES
PRECIPITATION
PRESSURE RANGE MEGA PA 01-10
PRESSURE RANGE MEGA PA 10-100
SILVER ADDITIONS
STEADY-STATE CONDITIONS
STRAINS
STRESSES
TEMPERATURE DEPENDENCE
TEMPERATURE RANGE 0400-1000 K
TIN ALLOYS
TRANSITION TEMPERATURE
X-RAY DIFFRACTION