The Philadelphia industrial area

✍ Scribed by T.K.C.

• Publisher: Elsevier Science
• Year: 1932
• Tongue: English
• Weight: 59 KB
• Volume: 213
• Category: Article
• ISSN: 0016-0032
• DOI: 10.1016/s0016-0032(32)90477-3

✦ Synopsis

459

grow older. Some will age-harden at room temperatures others must be held at higher temperatures. A single day is often adequate to bring about these desired changes in mechanical properties, although slight changes may continue to occur for a month. This so-called age-hardening consists in the formation throughout the metal or alloy of large quantities of extremely fine, sub-microscopic particles of the hardening constituent. These particles are less than I/IOO,OOO of an inch in diameter and are formed from the constituents of the alloy itself. The condition of the hardened alloy is very similar to that found in the alloy, " babbitt." That is, large numbers of very hard particles are embedded in a matrix of softer material.

T. K. C.