Lohmann LO-R 4528 Stainless Steel (N690 Equivalent)
R730.00 – R1'980.00
Lohmann LO-R 4528 Stainless Steel is an equivalent of Bohler’s popular N690 knife steel.
A Good martensitic stainless steel with good edge holding ability at a recommended working hardness 58-60HRC. It is used for all kinds of shaped and flat knives in the food processing industry, e.g. cutter knives and knives in the fish-processing industry.
Similar to Takefu VG-10 steel, which is a very popular steel for kitchen knives, fixed blades and folders. It has 17% Chromium vs. 14% in VG-10, which makes it considerably more stain resistant, but a bit less tough.
Thickness may vary slightly. 3,3mm – 3,6mm & 4,2mm – 4,5mm
***Stock obtained within 1-3 working days
Corrosion-resistant steels are characterised by increased resistance to acids and corrosion. They are basically divided into the categories of austenitic, ferritic, and martensitic steel.
Martensitic corrosion-resistant steels offer high protection against corrosion in the hardened state, excellent wear resistance, and outstanding cutting edge retention.
Austenitic corrosion-resistant steels offer very good corrosion resistance and very good hot and cold form-ability. They are generally cryogenic steels.
Ferritic corrosion-resistant steels are generally low in nickel and exhibit high resistance to chloride-induced stress corrosion cracking.
Heat Treatment Specifications for Lohmann LO-R 4528 Stainless Steel:
Soft Annealing: 800 – 850°C, Furnace cooling <550°C, then air cooling
Hardening: 1000 -1040°C, Oil quenching in a MEDIUM oil, we recommend PQ20 (DO NOT use vegetable oils, it is not designed for this process, and you will not get the constant results you need)
Tempering: 240 – 300°C, (preferred tempering range), for 55 – 58 HRC 460 – 480 °C, (increased toughness, but reduced corrosion resistance)
For the tempering diagram see: https://www.lohmann-stahl.de/fileadmin/redaktion/downloads/1.4528.pdf