... 7.93 g / cm-3 specific heat C (at 20 DEG C) 0.502 J - (g, c) - 1 thermal ... following temperature / DEG C) 20 100 500 12.1 16.3 21.4 line expansion coefficient alpha / (10-6/ DEG C) (in ... the following temperature / DEG C) 20 to 100 20 to 20 ... and the melting point of the M-1 1398 ~ 1420 DEG Ccharacteristic:A. dimensional accuracy is high, up to + 0 ...