In this investigation produce of API 5L-X70 with 100% DRI have been evaluated . For produce of this steel didn’t use of Niobium and only used to Titanium and Vanadium, also copper, nickel and chroum substitute with Molibdenium. Steelmaking process was done in a induction furnace. The steelmaking process was contain dephosphorization, decarburization, deoxidation and alloying, after that samples preaper from ingots for hot rolling. The samples have been rolling with laberatory hot-roll mill in 850°C-1100°C and 700°C-950°C temperatures and following that cooling in air. Microstructure of the samples study with optical metalugeraphy and SEM and mechanical propertises study with tensile test and charpy impact test. The results of this investigation has been defined that with used of Mo-Ti-V alloy system in both of rolling conditions can arrived to X70 mechanical peropertises but the sample wich rolling in lower temperature has higher yield strength than another. The main reason of this problem is grains refinement as the result of rolling bellow recrystallization temperature. The other reason is presipitation of V(C,N) during austenite to ferrite teransformation and prevention of grains growth. As well rolling in bellow recrystallization temperature influence on toughness.
