A high performance wear and impact resistant steel

Bozhong  8000 is a high performance wear resistant steel, exhibiting a wear resistance 50% higher than conventional 500HB water quenched steel, combined with excellent weldability and very acceptable workability. Rather than relying exclusively on a high hardness level, properties of Bozhong 8000 are improved as a result of the combination of an enriched alloying content (chromium, nickel, molybdenum and titanium) and specific heat treatment procedures.

The moderate hardness of Bozhong 8000 in the as delivered condition makes processing operations like cutting, machining and forming easier and far better than ordinary water quenched steels. When in service, Bozhong 8000 strongly improves its wear resistance by a surface hardening effect of about +70 HB under the action of local plastic deformations caused by impact with rocks or pressure by the abrasive particles. Bozhong  8000 is ideal for applications in mines and quarries, cement and steelmaking industries, public works and agricultural machinery. In the toughest industries such as mining and earth moving, the higher resistance to wear and impact abrasion translates into increased service life of wearparts and components made of Bozhong 8000 against conventional water quenched steels.

As a result, significant costs saving benefits are achieved to plant maintenance budgets. The grade is suitable for all types of abrasion, sliding or impact, dry or wet environments, including operating temperatures up to 350-450°C.

Standards
Bozhong 8000 is a proprietary and exclusive grade developed by Bozhong. There exists no engineering standard for plates intended for wear resistant applications.

Chemical Analysis
Typical values (weight %)

C	S	P	Mn	Ni	Cr	Mo
≤ 0.28	≤ 0.005	≤ 0.018	≤ 1.6	≤ 1.0	≤ 1.6	≤ 0.40

Mechanical Properties

	Hardness (HB)	YS MPa (ksi)	UTS MPa (ksi)	Elongation %	KCVL – 20°C (-4°F) J (ft.lb)	E GPa
Indicative values	470	1250 (181)	1630 (236)	12	44 (32)	205

Guaranteed values (as supplied) Hardness 430-500 HB

Metallurgical Concept

500 HB water quenched steel Conventional route Passive steel	Creusabro®8000 Alternative route Active steel
Restricted alloy elements (mainly C, Mn, B) Drastic water quenching Fully martensitic structure	Specific chemical composition Controlled cooling Martensite + bainite + retained austenite Perfect balance: high wear resistance + improved workability Wear resistance in service is a combination of: work-hardening (TRIP effect) Presence of micro-carbides (chromium, molybdenum, titanium) Delayed tearing of metal particles (super-ductility of the retained austenite).
Wear resistance in service is a result of the hardness in the as delivered state. It is an answer for common applications	Bozhong8000 is an answer for specific applications.