Stainless Steels: Properties:

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2 Stainless Steels: Stainless steels represent a group of steels which are distinguished by a special resistance to chemical attack of aggressive media. The Chromium content is the element responsible for this corrosion resistance. A Stainless steel should have a chromium content in excess of 12.8% which allows for the regeneration of a passive layer which protects the steel from corrosion. Stainless steels also contain a number of other elements which improves the materials physical properties such as wear resistance, the material s ability to hold an edge, toughness as well as polishability and machinability. Martensitic stainless steels have elevated carbon contents which allows it to be heat treated. This brings specific properties to light which are sought after by many industries such as medical, tooling and knife making. Properties: Martensitic chromium steel with additions of molybdenum and vanadium and a unique rolling process. High hardness and wear resistance without sacrificing corrosion resistance. Application: Cutting tools of all kinds requiring excellent corrosion resistance such as surgical instruments and other knives including detergent resistant cutlery which requires high cutting hardness and toughness. This material is also suitable for wear resistant Chemical Composition: Carbon Silicon Manganese Cobalt Chromium Molybdenum Vanadium Min Max Hot Forming Forging : C Heat Treatment: Microstructures Annealing : C (Ferrite+Carbide) Stress Relieving* : C (req. if >10% of material has been removed) Hardening* : C (Martensite+Carbide+traces of Austenite) Sub-Zero Quench* : Required (Minus 15 C) (Martensite+Carbide) Tempering* : Refer to chart (Tempered Martensite) Quenching media : Oil (agitate) Average Hardness : HRc Hardness range : HRc *1 hour per 30mm thickness once desired core temperature has been reached

3 Physical Properties: Density : 7.70 kg/dm 3 Modulus of Elasticity : 20 C Thermal Conductivity : 15 W/(m.K) Specific Heat Capacity : 430 J/(kg.K) Härten / Hardening Spannungsarmglühen / Stress relieving ÖL Oil Ofenabkühlung Cooling in furnace Anlassen auf Arbeitshärte Tempering to working hardness Sub Zero Abschrecken Sub Zero Quenching Reinigen / Härteprüfen Cleaning / Hardness test Note: For added strength of material, a sub-zero quench should occur between the hardening and tempering. Since only minus 15 C is required, this can be done in most domestic deep freezers capable of reaching minus 20 C. A Double Temper is recommended. To achieve an exact hardness, the first temper should be performed for a slightly (within 5% deviation) higher hardness. The hardness is measured after the first temper and based on the hardness achieved, the second temper is based on corrective tempering Tempering for best combination of wear resistance and corrosion resistance Tempering for best combination of wear resistance and toughness Tempering Chart

4 1200 TTT Diagram for Panzer36 Including Martensite, appropriated for knifemaking Austenite 900 Temperature ( ) C Austenite Ferrite + Carbide Martensite Start Retained Austenite Martensite 50% Martensite 99.2% 1 2 Time (s) Comparisons Edge Holding Wear Resistance Toughness Polishability ATS-34 Panzer36 154CM 12C27 19C27 440C N690 D2 In addition to it s composition, the advantage of Panzer36 is brought about by its unique production process which was designed to yield the best of the best properties when compared to its competitors materials. The Panzer36 is not continually rolled, but instead cross rolled to cancel out residual stresses incurred during the production process. Panzer36 therefore has a significant advantage over its competitors due to it s dimensional stability during laser cutting and heat treatment. The Panzer36 material grade is officially distributed by the SA company: Knife Machines and Tools cc Telephone: /1 info@kmts.co.za Web Site:

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6 Panzer36 Test Report Panzer36 - just about indestructible! To prove the worthiness of any product, it needs to be deliberately tested to destruction, in a controlled environment. This is exactly what Knife Machines and Tools did, prior to introducing Panzer36 to the Knifemakers market. We proudly confirm that the second knife above was subject to the following tests: Hair shave and paper cut: The knife passed this test with distinction. Rope cut: Cut a 25mm thick free hanging sisal rope with a single stroke. Performed three successful cuts. Edge geometry and sharpness test passed. Sisal strand cut: Cut individual strands on a cutting board until blade is blunt. The edge was still sharp after 250 cuts. The operator quit, not the knife! Edge geometry & sharpness test passed. Wood beam chop: The knife was used in a chopping motion to cut a 38mm x 114mm roof beam. Standard requirement is two cuts. The edge was still shaving sharp when operator quit after chopping through the beam ten times! Nail cut: Blade was used to cut a 100mm and a 160mm nail with blows from a hammer. 10mm mild steel round bar cut: The blade was used to cut a 10mm mild steel rod with blows from a hammer. Here the 0.5mm cutting edge failed and chipped. Various cool drink cans and plastic bottles were satisfactorily sliced. Flex test: The blade is required to flex at least 20 degrees and return to straight when flexed in a vice. The test knife recovered perfectly straight after 30 degrees and deformed only by 4 degrees after a 40 degree bend. Bend test: The requirement is that the blade is bent at least 90 degrees where after it should recover to at least 45 degrees. The test blade did all this, and more... it recovered to 8 degrees after being bent to 90 degrees. The camping knives shown above were designed, built and tested by Kevin Harvey, a member of the Knifemakers' Guild of Southern Africa since 1991 and also a Master Bladesmith with the American Bladesmith Society since 2003.