All-round excellence combined with cost-competitiveness – get to know Core 4622

Core 4622 is an exceptionally versatile nickel-free ferritic grade with excellent cost stability and good corrosian resistance. This adaptable grade is suitable for a wide variety of applications including kitchenware, automotive parts, and industrial process equipment.

Core 4622 is a highly cost-competitive and price-stable alternative to traditional nickel-alloyed austenitic grades such as 304L, offering the same well-balanced material properties while eliminating the price fluctuations associated with nickel.

“With no nickel or molybdenum, Core 4622 is cost-competitive in the long term and just as versatile as 304L,” says Juha Kela, Senior Product Manager, Outokumpu. “This established grade is a true all-rounder, with good corrosion resistance, excellent deep-drawability and easy polishing, plus good welding and machining characteristics.” 

The high typical chromium content of 21% gives Core 4622 good corrosion resistance, with localized pitting resistance as good as, or even better than, austenitic grades like 304L. Core 4622 has the added advantages of less springback, making designing and shaping easier, and better thermal conductivity than comparable austenitic grades.

Versatile and easy to process

As well as good corrosion resistance, Core 4622’s high chromium content means this grade is a viable alternative to standard austenitic grades in a huge variety of applications. For example, it can be used for kitchenware like pots and pans and appliances such as dishwashers and refridgerators. It is also suitable for indoor and outdoor building applications, tubular products for the automotive industry, and process industry equipment such as heat exhchangers.

“Core 4622 has excellent all-round mechanical properties, particularly with regard to deep-drawing. It has a higher R-value and a higher limited drawing ratio (LDR) than 304L,” explains Kela. “Furthermore, Core 4622 is virtually roping-free, which makes it very easy to polish. This is a key advantage especially in applications where the aesthetic properties of the materal are as important as its technical performance after forming.”  

Core 4622 can be formed using typical processes including folding and bending. The grade also has excellent machinability and weldability compared to austinitic grades. Its lower work hardening speeds up machining and reduces tool wear. In terms of weldability, Core 4622 can be easily welded with conventional methods using argon or helium-based shielding gases and 316L filler metals. It exhibits less welding distortion due to its excellent heat transfer properties and requires no post-weld heat treatment. 

Availability, standards, and approvals

Core 4622 is available as cold rolled coil and sheets, and in thicknesses of 0.3 – 4.5 mm and widths up to 1500 mm. In hot rolled form it is available in thicknesses of 3 – 5.5 mm and widths up to 1500 mm. The grade is covered by the ASTM 240/A240M, ASME SA-240/S-240M, PED Directive 2014/68/EU, and EN 10028-7 standards, and is also included the new EN 10088-2 standard.