Consider a turning operation performed on steel whose hardness = 225 HB at a cutting speed = 2.2 m/s, feed = 0.28 mm, and depth = 4.0 mm. Using values of thermal properties found in the tables and definitions of Section 4.1 and the specific energy value from Table 17.2, compute an estimate of cutting temperature. Assume ambient temperature = 20C. From Table 17.2, U = 2.2 N-m/mm = 2.2 J/mm, from Table 4.1, p = 7.87 g/cm = 7.87(10-) g/mm, from Table 4.2, C = 0.460 J/ g C, and From Table 4.2, thermal conductivity k = 0.046 J/s mm C. Answer: