Grade 14320 is fi ne-grain steel which is used for rolling of plates for production of parts exposed to extreme abrasion and mechanical wear.

These plates can be used for transport routes and chutes for gravel, stone, coal, cement etc. Resistance against abrasion, and hardness are guaranteed either in the condition without heat treatment (so called as rolled – 14320.0), or after quenching.

Machining in the condition without heat treatment (14320.0) is diffi cult; in the soft annealed condition (14320.3) it is good. Cold forming is not possible, hot forming at temperature of 850–1,150 °C is good.

Joints between parts are usually made as bolted joints; or in the form of fi xing welds, using preheating up to 200 °C at minimum (thickness up to 10 mm without preheating); however the welded joint does not reach the strength of the parent base. Cutting plates by means of fl ame cutting, or fl ame cutting shaped plates is also performed with preheating up to 200 °C at minimum. Shearing is not recommended for plate cutting.

These plates can be delivered as semi-trimmed plates having thickness from 8 to 25 mm in the condition without heat treatment (14320.0), or from 8 to 30 mm in the soft annealed condition (14320.3). Other thickness and dimension on agreement.

Tensile strength (Rm) in the condition without heat treatment (14320.0) is approx. 930 to 1,370 MPa, the lowest yield strength (ReH) is approx. 75 % of the tensile strength, the lowest elongation (A5) is 8 % and Brinell hardness is approx. 270 to 400 HB. Tensile strength can be improved to approx. 1,400 MPa by quenching. Tensile strength, yield strength, and elongation are not subject to testing and acceptance inspections because test samples are diffi cult to be made.

In the soft annealed condition (14320.3) the Brinell hardness is max. 260 HB.