DEVELOPMENT OF MICROALLOYED HIGH-CARBON STEELS FOR PLOW DISKS

Plough disks are often made of high-carbon steels with small additions of chromium (0.40 to 0.60 %), in the as-quenched and tempered conditi on, As a consequence, they combine wear resistance with the tensile, f atigue, and impact strength necessary to withstand extremely adverse w ork conditions, In an effort to produce steels for this use with impro ved mechanical properties, four different steel compositions, all micr oalloyed with niobium, were produced for the present work, Two steels kept the basic chromium content of the commercial alloy (0.40 to 0.60 %), while this element was replaced with manganese in the other two st eels. The chromium and manganese steels were produced with two levels of niobium. The Jominy hardenability, tensile properties, and impact a nd wear resistance of these materials were evaluated, A microstructura l characterization was also performed. The results show that the devel oped steels can have the required hardness and strength levels, The hi gh-niobium steels showed the best wear resistance but the poorest impa ct toughness, The wear resistance of the low-niobium steels was slight ly higher and the impact toughness slightly lower than in the commerci al alloy, The low-niobium steels show potential for commercial use.