THE CHARACTER AND SIGNIFICANCE OF THE COLD-BEND TEST. 



"The test of the ductility of a malleable metal by bending it cold is the most common and 

 perhaps the most useful of all the tests which can be applied to it. For wrought iron and struc- 

 tural steel this test approaches more nearly to the severe usages of actual practice than does the 

 tension test with its elastic limit, ultimate strength, elongation, and reduction of area. It is not 

 so easily standardized, however, and it is employed less in America than in Europe, partly be- 

 cause no standard methods and results have been agreed upon here. 



"If a sample of wrought iron or steel will, when 

 cold, fold upon itself absolutely, or make the double fold 

 (as shown in accompanying sketch), there can be no doubt 

 of its high quality. When it fractures, however, at inter- 

 mediate stages of this process, the question of its quality 

 is left in doubt, and some standard limit is required if this 

 test is to be made the basis of acceptance. The great ad- 

 vantage of this test is that it can be made at any time in 

 the shop, without the expense attaching to tension tests, 

 and by the man who uses or makes up the material." John- 

 son, "The Materials oi Construction" (1906), Page 394. 



"The cold-bend test is one that has been known from 

 the earliest times and which is constantly used in all mills 

 where wrought iron or steel is produced. The bending of 



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