FORD FLTM EU-BQ 051-1-2000 DETERMINATION OF BRITTLENESS OF HIGH STRENGTH BOLTS BY STRESS CORROSION TESTING.pdf

1、 FORD LABORATORY TEST METHOD EU-BQ 051-01 Date Action Revisions 2000 11 09 Editorial no technical change A. Cockman 1994 02 28 Printed copies are uncontrolled Page 1 of 2 Copyright 2000, Ford Global Technologies, Inc. DETERMINATION OF BRITTLENESS OF HIGH STRENGTH BOLTS BY STRESS CORROSION TESTING Ap

2、plication This method is used to determine the brittleness of high strength bolts (with a hardness of more than 310 HV) caused by phosphate diffusion. Apparatus Required Clamping Device (Figure 1) Torque Wrench Salt Spray Cabinet (according to ASTM B 117) Conditioning and Test Conditions All test va

3、lues indicated herein are based on material conditioned in a controlled atmosphere of 23 +/ - 2 C and 50 +/ - 5 % relati ve humidity for not less than 24 h prior to testing and tested under the same conditions unless otherwise specified. Procedure The bolts to be tested have to be dipped into a 5 %

4、NaCl solution prior to assembly. Assemble the bolts in a test device acco rding to Figure 1 so that the 0.2 % yield strength of the bolts is reached. This can be achieved by use of yield control meters, e.g. SPS Unbrako or by accurate load/extension techniques. Place the assembled test device into t

5、he salt spray cabinet for a minimum of 48 h with the bolts in a horizontal position. Evaluation Re - torque the bolts after testing to the 0.2 % yield strength. Failure is determined as any bolt fracture. Chemicals, materials, parts, and equipment referenced in this document must b e used and handled properly. Each party is responsible for determining proper use and handling in its facilities. FORD LABORATORY TEST METHOD EU-BQ 051-01 Pa ge 2 of 2 DETERMINATION OF BRITTLENESS OF HIGH STRENGTH BOLTS BY STRESS CORROSION TESTING