Specifications of A4 rebars show that these rebars have higher durability and strength than rebars A1, A2, A3, but due to the lack of high-tech facilities and technology and use of insufficient high carbon steels, Production of A4 rebar was not possible. Today, with the advancement of technology and the construction of the Tremax system, industries can control the temperature, the cooling rate of low carbon steel ingots, to produce 520 and higher tread, so that there is no need to worry about stability and impact strength. More over shows desirable mechanical characteristic (easy ductility). rebar A4 Ribbed rebar 500 and 520 are called A4 rebar.
