Wear Protection with Borocoat-Diffusion Layers

1 Wear Protection with Borocoat-Diffusion Layers Outline Brief Brief Introduction Introduction to to Heat HeatTreatments Treatments Boronizing Boronizing Properties Properties Applications Applications Boronizing Boronizing agents agents -2- Surface Treatments Thermo- Thermo- Thermal Thermal Gas Gasphase phase Galvanic Galvanic chemical chemical Flame Hard Chrome Carburizing CVD. hardening plating Induction Nitriding PACVD Nickel plating hardening Electron beam Boronizing PVD Zinc plating hardening -3- Heat Treatment Overview Diffusion Diffusion annealing annealing Hardening Hardening Tempering Tempering treatments*. treatments*. Recrystallization Recrystallization Through Throughhardening hardening <200 C. <200 C Nitriding Nitriding annealing annealing Stress Stressrelief relief Surface Surfacehardening hardening >500 C. >500 C Carburizing Carburizing annealing annealing Secondary Secondary Soft Softannealing annealing Boronizing Boronizing (>480 C).

2 (>480 C). Normalizing Normalizing Age Agehardening hardening Oxidizing Oxidizing Diffusion Diffusionannealing annealing -4- Coatings (CVD, PVD, Thermal ). Boundary between coating and steel substrate Coating Functional layer develops on top of the substrate . Moderate adhesion . High stresses on interface -5- Diffusion Processes ( Boronizing ). Atoms Functional surface is developed within the material . Superior adhesion . Low dimensional changes -6- What is Boronizing? Boronizing Boronizingisisaathermocemical thermocemicalsurface surfacetreatment treatmentin inwhich which Boron Boronatoms atomsdiffuse diffuseinto intothe thesteel steelsubstrate substrateand andform formaa very veryhard hardBorocoat-layer. Borocoat-layer. Boronizing Boronizingeasily easilytops topsthe theperformance performanceof ofcommonly commonly used usedmethods methodssuch suchas ascarburizing carburizingor ornitriding.

3 Nitriding. -7- Properties of Borocoat Layers --High Highhardness hardness1400-2600. 1400-2600HV, HV,even evenon onnon-alloyed non-alloyedsteels steels --Diffusion Diffusiondepth depth10-250. 10-250 m m --High Highabrasion abrasionresistance, resistance,resistance resistanceagainst againstcold coldwelding welding --Excellent Excellentthermal thermalstability stability --Self Selflubricating lubricatingeffect effectat athigh hightemperatures temperatures --Superior Superiorbonding bondingstrength, strength,no nocoating coatingbut butdiffusion diffusionlayer layer --Good Goodresistance resistanceagainst againstmolten moltenmetals metals(Al, (Al,Zn). Zn). -8- Material Selection for Boronizing --Non Nonalloyed alloyedand andlow lowalloyed alloyedsteels. steels. --Stainless Stainlesssteels steels --Cast Castiron, iron,casted castedsteel steel --Cold Coldwork, work,hot hotwork workand andHSS.

4 HSSsteel steel --Powder Powdermetallurgical metallurgicalsteels steels --Cobald Cobaldbased basedmaterials materials --Cemented Cementedcarbides carbides --Nickel-based Nickel-basedalloys alloys(Nimonic . (Nimonic , ,Inconel , Inconel ,Hastelloy , Hastelloy ,Haynes ). Haynes ). Boronizing Boronizingisisthe themost mosteffective effectivewear wearsolution solution for forNickel-based Nickel-basedalloys! alloys! -9- Applications --Automotive Automotivecomponents components(turbo (turbocharger chargerengineering). engineering). --Oil Oiland andgas gasindustry industry(valves (valvesand andaccessories). accessories). --Power Powerplant plantengineering engineering --Toolmaking Toolmakingand andmetal metalforming formingtechnology technology --Plastics Plasticsprocessing processing --Glass Glassproduction production --Gear Gearmanufacturing manufacturing --Components Componentsfor fortextile textilemachinery machinery --Aluminum Aluminumprocessing processing --Mechanical Mechanicalengineering engineering -10- Boronizing - Setup- Metal Metal Box Box Ekabor.

5 Ekabor Boronizing Boronizing powder powder Furnace Furnace -11- Box for Boronizing Gas outlet Top cover Sealing annealing box Protective gas inlet Material AISI 314 ( ). -12- Box for Boronizing -13- Parts Preparation Sample for quality control Part Container Boronizing powder (Ekabor2). 15mm -14- Parts Preparation -15- Batch for Boronizing packed in a Box -16- Batch for Boronizing packed in a Box -17- Properties of Borides FeB Fe2B. % Bor 16,23 8,83. Lattice Structure rhombic tetragonal Stress after cooling down Tension Compressive Coefficient of Linear 23 7,9-9,2. Expansion10-6/K. Hardness [ ] 1900-2100 1650-2000. Density [g/cm3] 6,75 7,43. Modulus of Elasticity [GPa] 343 284. Thermal Conductivity 12 30. [W/mK]. 2 -18- Boronizing Layer (Iron matrix has been etched off, only boronized layer structure is visible). Former Formersurface surface 9. -19- Microsections of Boronized Steels Armco (pure) iron AISI 1015 / /C15.

6 AISI 5115 / / 16 MnCr5. -20- Microsections of Boronized Steels AISI D-6 / / X210 CrW12. Cold work steel AISI 4140 / / 42 CrMo4. Tempering steel AISI 314 / Hot work steel -21- Microsections of Boronized Nickel-Based Alloy Hastelloy . Hastelloy C4. C4/ Nickel-Based Alloy Nickel-Based Alloy Hardness before boronizing: 425 Hardness boronized: 1715 -22- Wear Comparison of AISI 4131. Ball-disc test (FN=17N, 500m). -23- Corrosion of high alloyed Steel in molten Zink untreated Weight loss [g/cm2]. boronized Tsipas et al Time [h]. -24- Corrosion Resistance of Boronized vs Untreated Steel AISI 1045 (Ck45) at 56 C. untreated Weight loss [mg/cm2]. boronized time [h|. -25- Lifetime comparison of boronized and nitrided extruder screws Nitrided Boronized GF=amount of glass fibres -26- Boronized Extrusion Screws -27- Boronized Ball Valves (Stainless Steel). Material AISI 316. Hadness base material: 315 HV.]

7 Hardness boronized 1950 HV. -28- Ball Valves -29- Boronized Burner Nozzle -30- Boronized Automotive Parts Oil pump gears Only teeth boronized Hardness 1700 HV. Depth 40 m -31- Boronized Parts for Glass Bottle Production Prevention of sticking (glass-metal). -32- Boronized Parts for Glass Bottle Production -33- Boronized Filters Stainless Steel Hardness before: 285HV. Boronized: 1800HV. Prevention of Abrasion -34- Boronized Pump Part Inconel . Hardness before: 425 HK. Boronized 2880 HK. Depth 50 m -35- Boronized Compressor Wheel Inconel 625. Hardness before: 396 HV. Boronized: 2715 HK. Depth: 60 m -36- -37.