At 700°C, with strain rates (έ) of 0.02, 0.05 and 0.08 min−1, the superplastic m-δ curves of T10 steel determined were all of the type (the general type). Their Values of rr (0.241 → 0.252 → 0.267), mL (0288 → 0.241 → 0.252 ),mF (0236 → 0.251 → 0.268), δL(38→. 535 →.58%), and δF (84.7 → 92 → 99%) all increased with increases in value. At the same temperature with έ =0.1 min−1, an ascending type of curve, mL=mwn = mo(=0.245)<mx (=.0.249), δo (=0)= δL > δx (=94%) was obtained from the transformation of δL and mL into the δF and mL of the general type of curve. Similar results have been obtained at 730°C.

At 600°,650°, 700° and 730°C, with έ =0.05 min−1 the same general type of curves were obtained. Their values of mo. (0.213 → 0.230 → 0.252 → 0296), mL (0.19 5 → 0.208 → 0.241 → 0.256 ).mF (0.204 → 0.234 → 0.251 → 0.280). δL (44 → 49 → 53.5 → 63.5%)and δF (77 → 81 → 117 percnt) increased with increases in temperature. For the same strain rate, while at 780°C, an ascending type of curve, mL.= mmis = mo (= 0.198) < mF (0.236).δo (=o) = δL < δx (=73%)was obtained from the transformation of the general type of curve in the same way as mentioned above.

The shape constants, C values, which vary with strain have been calculated.

Symbols: Refer to the List of Symbols.