Stress Rupture of Lead-Free Soldered Joints Used to Assemble Copper Plumbing Systems

Published

November 1, 1999

Author(s)

Richard J. Fields, D A. Shepherd, A Cohen, A Kireta

Abstract

In 1993, the National Institute of Standards and Technology (NIST), formerly NBS, was engaged to develop the necessary elevated temperature allowable stress data for soldered copper joints using Pb-free Alloys Sb5, E, and HB of ASTM B32. The NIST testing procedure and data generated are the bases of this paper. In this work, stress rupture lifetimes of soldered sleeve joints in Type L copper water tube under longitudinal load were obtained over the range of 38 degrees C to 121 degrees C (100 degrees F to 250 degrees F) in air for durations exceeding one year. The stress/lifetime curves for allow SB5 are in excellent agreement with the limited data that were available from previous NBS and other studies, thus validating the test procedure and indicating that the measured strengths are not sensitive to specimen design, soldering technique of test procedure. New joint strengths based on the current NIST studies are presented in this paper. The extensive data bases for all three lead-free solders permit the use of a less demanding safety factor more in accord with that originally employed for Sn50, a lead-containing solder.

Citation

Welding Journal

Volume

78

Issue

No. 11

Pub Type

Journals

Keywords

copper plumbing systems, lead-free solder, long-term behavior, mechanical properties, solder joints, strength

Citation

Fields, R. , Shepherd, D. , Cohen, A. and Kireta, A. (1999), Stress Rupture of Lead-Free Soldered Joints Used to Assemble Copper Plumbing Systems, Welding Journal (Accessed July 26, 2024)