The quality of steel is a critical factor in the production of Industriemesser. The metal must maintain blade sharpness under intense loads, resist rust when exposed to moisture and chemicals, and remain stable at temperatures up to 550°C.
Requirements for Steel
The manufacturing of industrial knives demands compliance with specific quality standards. The quality of the metal and other parameters are governed by GOST R 51015-97. Key requirements include:
- Blade Cross-Section: In the transverse direction, blades must have one of the following cross-sections: wedge-shaped, rectangular, or rectangular with a chamfer of 5 mm or more.
- Blade Sharpening: Blades must be sharply honed at an angle of 30 to 50 degrees. Up to 20 mm from the handle, the blades should be blunted.
- Härte: Blades must be resilient with a hardness of at least 49 HRC. A reduction to 41.5 HRC is permitted up to 15 mm from the handle, and knives with corrugated blades may be produced without heat treatment.
- Straightness: The allowable deviation must not exceed 1 mm per 100 mm of length.
Types of Steel
For the production of industrial knives, alloyed, medium, or high-carbon steels are used. The primary grades include: SKD-11, SK5, HSS, 9CrSi, SUJ2, and 40Х13.
HSS
High-speed steel with a chemical composition of 3.5–18% tungsten, 0.6–1.5% carbon, 0–5% molybdenum, 0–5% vanadium, and 0–10% cobalt. In its hardened and tempered state, HSS achieves a hardness of 60–67 HRC. The cutting properties and hardness of the knives remain intact at temperatures up to 600°C, which is essential for high-speed cutting processes. It is used to manufacture saw blades, countersinks, milling cutters, dies, and drills (spiral, step, and core).
40Х13
Stainless, heat-resistant steel primarily used for manufacturing knives that operate in aggressive environments at temperatures up to 450°C. During quenching, 40Х13 steel reaches a hardness not exceeding 55 HRC.
It is employed to produce knives for Lebensmittelverarbeitung, as well as surgical instruments and equipment for the chemical industry. This steel has limited resistance to temperatures above 450°C, restricting its use in welded structures. Knives made from 40Х13 have a soft cutting edge, necessitating regular sharpening.
SK5
A Japanese carbon tool steel used to create knives for applications where heating of the cutting edge is avoided during contact with metals, polyethylene, wood, or plastic. After quenching, its hardness does not exceed 62 HRC.
SK5 is utilized for knives subjected to elastic loads, such as spring plates and disks. It is also used to manufacture saws for woodworking and cores for casting molds.
9CrSi
Alloyed tool steel designed for knives working with soft materials. It contains approximately 0.95–1.25% chromium (Cr) and about 1.5% silicon (Si). Chromium enhances hardenability, reduces carbon oxidation, and increases corrosion resistance, while silicon boosts hardness and elasticity.
With a hardness of 62–63 HRC, it ensures excellent resistance of the cutting edge to dulling. It is used in the production of blades for woodworking, including crushing, peeling, and keyway blades.
SUJ2
High-carbon chromium bearing steel per the Japanese JIS G4805 standard. Its high carbon (0.95–1.10%) and chromium (1.30–1.60%) content provides hardness and wear resistance under elevated loads. Manufacturers use this grade for counter knives, disc, and plate knives due to its ease of processing and relatively low cost compared to SKD-11 and HSS.