الفهرس 
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Abstract
The following conclusions are obtained;
I. Cold and hot work tool steels as received materials represented the lowest hardness and the highest friction coefficient and wear.
2. For cold work tool steels, hardness of both heat treated specimens quenched in oil and normalizing represented the highest hardness values (61.6 HRC) and (63.7HRC) respectively.
3. For cold work tool steels, the highest wear resistance and the lowest values of the friction coefficient were observed for both heat treated specimens quenched in oil and normalizing.
4. For hot work tool steels, the hardness of heat treated specimen quenched in salt bath at 500°C and tempered at 500°C represented the highest hardness value (50.3 HRC) which is higher than oil quenched specimen followed by tempering at 500°C (47.3 HRC).
5. For hot work tool steels, the highest wear resistance and the lowest values of the friction coefficient were observed for heat treated specimen quenched in salt bath at 500°C and tempered at 500°C.
6. The hardness of cold work tool steels decreases with increases of tempering temperature. At lower tempering temperatures, there were nominal effects on hardness, but as tempering temperature goes up, the effect of tempering temperature on its hardness becomes prominent.
7. The hardness of hot work tool steels increases with increases tempering temperature up to 500°C but as tempering temperature increases more than 500°C, the hardness decreases.
8. The optimum tempering temperature for both cold and hot work tool steels is 500°C, which significantly improves hardness and wear resistance.