310HCbN  is premium Nb-N composite strengthened 25-20 austenitic heat-resistant stainless steel bright bar. Optimized based on 310H high Cr-Ni matrix, carbon controlled 0.04%~0.10%, Cr 24~26%, Ni 19~22%, with combined Nb 0.2~0.6% and N 0.15~0.35%, specially developed for ultra-supercritical thermal power and high-temperature high-pressure steam serviceiBaosteel.
Dispersion strengthening from nano Nb(C,N), NbCrN precipitates and M₂₃C₆ carbides delivers far superior stress rupture & creep resistance at 600~750℃ versus 310S, 310H and Super304H, resisting creep deformation and fracture under long-term high-temperature pressure. Niobium locks carbon to drastically reduce intergranular corrosion sensitization after welding and long-term heating, forming dense non-spalling oxide scale with outstanding resistance to high-temperature steam oxidation, sulfidation and carburization.

Chemical element content (%)

Specification：1.00~300.00mm

Application: It is mainly used to manufacture ultra-supercritical boiler superheater & reheater mandrels, high-temperature header bolts and flanges, thermal power high-temperature steam pipe fasteners, waste incineration high-temperature heat exchange valve stems, stressed bars for petrochemical cracking furnaces, high-temperature heat exchange tooling for solar thermal power stations, support shafts for heat treatment carburizing furnaces, high-temperature gas reactor bolts, 700℃ steam circulation valve spools, load-bearing power plant furnace fittings, etc.
Widely applied in supercritical & ultra-supercritical thermal power units, waste incineration waste heat boilers, petrochemical high-temperature cracking units, solar thermal heat exchange equipment, industrial carburizing furnaces, high-temperature high-pressure steam pipelines, metallurgical high-temperature heating equipment and other industries.

Core Advantages Over Competitors

1. High quality stability: Full closed-loop production and online spectral non-destructive inspection strictly control key alloy elements C, Cr, Ni, Nb, N with carbon stably limited 0.04~0.10% and precise Nb-N ratio. Uniform controllable austenitic grains and dispersed NbCrN precipitates ensure negligible batch fluctuation of high-temperature creep strength, steam oxidation resistance and weldability for consistent mass production of power station high-pressure high-temperature parts.

2. Excellent surface quality: Dedicated high-precision cold drawing and centerless grinding lines produce bars free of peeling, oxide scale, scratches and pits with mirror finish. Smooth surface reduces alternating thermal stress concentration under high-temperature steam service to greatly extend fatigue life of components operating long-term at 700℃; secondary polishing is unnecessary for most precision machining.

3. Ultra-high dimensional accuracy: Precision cold rolling mills and automatic online dimension detectors narrow tolerance range with tiny single-bar error and strong batch uniformity. Unified part specifications during automatic mass production significantly raise finished yield and machining precision.

4. Rich product variety: According to market demand and customer's special requirements, customized products are provided to meet the use requirements under various complex working conditions, providing customers with more choices.

5. Perfect after-sales service: The perfect after-sales service system can respond to customer needs and feedback in a timely manner. For problems encountered by customers during use, technical support and solutions are provided to customers quickly.

We mainly engage in cold heading wire, bar, peeled bar, and profiled bar; our products cover 11 series and more than 300 grades, and we continue to develop a variety of professional steels. We can provide all-round solutions such as cold heading finishing line manufacturing and high-precision bright bar customization, and provide one-stop procurement services and package procurement solutions for global customers. The website displays some grades. If you don’t have the grade you need, please contact us by phone or email.