INTERNAL FRICTION ASSOCIATED WITH MARTENSITIC TRANSFORMATION OF ASCAST MANGANESE-COPPER ALLOYS
铸态Mn-Cu合金的马氏体相变内耗的研究

Internal friction of martensitic transformation of as-cast manga-nese-copper alloys with Mn-content 90% was studied. Results show that the peak tem-perature of the stable peak (T=0) at low frequencies is independent of the mea-suring frequency, but the peak height decreases with increasing frequency. It is,therefore, not of a static hysteresis mechanism. The peak height is dependent onT and f at a constant heating or cooling rate, but it does not show a linear rela-tionship with T, 1/f or T/f. The peak height is independent of the strain amplitudein the range (A_e: 1×10~(-5)-1×10~(-4)). Consequently the low frequency internal fric-tion of martensitic transformation is not only a volume effect, but also a surfaceeffect connected with coherent boundaries.