In metallurgy, heat treatment is process of improving the characteristics of a metal, especially steel, by heating it to a high temperature, though below the melting point, then cooling it to a lower temperature. The process has the effect of toughening by lessening brittleness and reducing internal stresses. Suitable temperatures for tempering vary considerably, depending on the type of steel and designed application. The part after taking out from high temperature oven will be put in a warm oven. The temperature of part follows this equation: dT/dt=-k(T-Tm). high temperature oven To: 215C warm temperature oven Tm: 50 C A part taken out from high temperature oven was put into warm temperature oven immediately. After 120 mins its temperature drops to 85 C. Determine the time to let temperature drops to 65 C. Later, it is found that when the part is taken out from warm temperature oven, if the temperature of the part is between 60C and 62 C, the part fatigue performance is the best, design the working procedure (time in the warm oven). Due to some maintenance on the warm oven, the warm temperature oven Tm change to 49 C. Adjust your working procedure (time in the warm oven) to keep temperature of the part out is still between 60C and 62 C./nMake group in 2-3 students. Finish all calculation. Edit a computer software (Excel or MATLAB etc. all OK) application file to show the time-temperature relationship curve. (In real application, this can compare with monitor data and provide warning when something wrong.) Write a report on all the issue in this process.

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