VANCRON 40 eng-04 - Uddeholm

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VANCRON 40QUENCHING MEDIA•Vacuum furnace with high speed gas at sufficientoverpressure (2–5 bar)• Martempering bath or fluidized bed at approx.550°C (1020°F)•Forced air/gas.Note 1: Quenching should be continued untilthe temperature of the tool reaches approx. 50°C(120°F). The tool should then be tempered immediately.Note 2: For applications where maximum toughnessis required use a martempering bath or afurnace with sufficient overpressure.TEMPERINGFor cold work applications tempering shouldalways be carried out at 560°C (1040°F) irrespectiveof the austenitizing temperature. Temper three timesfor one hour at full temperature. The tool should becooled to room temperature between the tempers.The retained austenite content will be less than 3%after this tempering cycle.DIMENSIONAL CHANGESDimensional changes after hardening and tempering.Heat treatment: Austenitizing between 950–1100°C(1740–2010°F)/30 minutes and tempering 3 x 1 h at560°C (1040°F).Specimen size: 50 x 50 x 50 mm (2" x 2" x 2") and100 x 40 x 20 mm (4" x 1,5" x 1").Dimensional changes: growth in length, width andthickness +0,04% to +0,20%.SUB-ZERO TREATMENTPieces requiring maximum dimensional stability canbe sub-zero treated as follows:Immediately after quenching the piece could besub-zero treated to between –70 to –80°C (–95and –110°F) or in liquid nitrogen, soaking time1–3 hours, followed by tempering. Sub-zerotreatment will give a hardness increase of ~1 HRC.Avoid intricate shapes as there will be risk ofcracking.Surface treatmentsSome cold-work tools are given a surface treatmentin order to reduce friction and increase tool wearresistance. The most commonly used treatments arenitriding and surface coating with wear resistantlayers of titanium carbide and titanium nitride (CVD,PVD).Vancron 40 have been found to be particularlysuitable for titanium carbide and titanium nitridecoatings. The uniform carbide distribution inVancron 40 facilitates bonding of the coating andreduces the spread of dimensional changes resultingfrom hardening.NITRIDINGA brief immersion in a special salt bath to produce anitrided diffusion zone of 2–20 µm is recommended.This reduces the friction on the envelope surface ofpunches and has various other advantages.PVDPhysical vapour deposition, PVD, is a method ofapplying a wear-resistant coating at temperaturesbetween 200–500°C (390–930°F). As Vancron 40 ishigh temperature tempered at 560°C (1040°F)there is no danger of dimensional changes duringPVD coating.CVDChemical vapour deposition, CVD, is used forapplying wear-resistant surface coatings at a temperatureof around 1000°C (1830°F). It is recommendedthat the tools should be separately hardenedand tempered in a vacuum furnace aftersurface treatment.Note: Vancron 40 is designed to be used withoutsurface coating as it contains a high amount ofnitrogen.6
VANCRON 40WEAR RESISTANCEAdhesive wearWear resistance comparisonComponent: laboratory test stripTool type: blanking punchTool dimension: 10 x 40 mmWork material: 18/8 stainless steel SS 23311 mm thickVANADIS 4Wear loss, µm 2100008000600040002000VANCRON 40VANADIS 4 VANCRON 40TRIBOLOGICAL PROPERTIESResultsSteel / VANADIS VANADIS VANADIS VANCRONSurface 23 6 10 40coating uncoated uncoated uncoated uncoatedPartProduced 83 000 800 000 1 9000 000 >6 000 000Hardness HRC 62 64Failuremechanism Galling Still runningSteel / VANADIS 23Surfacecoating Salt bath nitriding PVD TiN CVD TiC/TiNPartProduced 160 000 130 000 2 000 000Hardness HRC 62Failure DelaminamechanismGalling tionCold forming die for producing a part of stainless steel forpump housing. Courtesy: Grundfos A/S, Denmark.7
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VANCRON 40 eng-04 - Uddeholm

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