Spheroidised steel is a heat treated steel which is used to increase the formability and blankability during processing of high strength steel - typically with Carbon content (C %) of 0.45 % and above. This results in steel with Carbon Steel Strip combining ease of fabrication with good strength and surface finish. Spring Steel Strips Grades : C-45, C-55, C60, C65, C70, C75, C85, HC-14, En 42 J, C-98, C-100, C-124 / HC21 etc.