Rust-free and long-lasting by functional coatings

Transcription

1 Rust-free and long-lasting by functional coatings Automotive Coatings Berlin Nov. 25th 2011 Protective Coatings September 13th Düsseldorf S. Goedicke, F. Groß, G. Frenzer, S. Sepeur NAN-X GmbH

2 verview Protective Coatings Use of transparent binder solution Sol-Gel-Process or SiliXan Binder Coating formulation with functional pigments, particles, fillers etc.

3 The sol-gel process R R Si R Hydrolysis + H 2 R H R Si H H Condensation - H 2 H H R Si R Si H H - Si--Si = glass-like inorganic network - R = H or functional group Evaporation of solvent and final crosslinking Further crosslinking after application to substrate nano condensates in solution

4 The sol-gel process - Moiety R = Network modifier, e.g. methyl, propyl, phenyl, dimethyl... Flexibilisation of the inorganic network by targeted integration of defects. - Moiety R = Network creator, organic moieties with functional groups such as epoxy, methacryl, isocyanato, amino... Creation of an additional organic network H H R Si H Me Me Me Me Me Me Me - Modification of nano particles, different function depending on type of particle, e.g., Ti 2, Al 2 3, Al(H), Ce 2, Zn, Zr 2, Fe 2 3 Example : Glass-like inorganic matrix and structuring by electrostatically stabilized nano particles H H

5 Stable Sol-Gel-Matrices Binders and their properties Modification CH 3 Solubility Alcohols, glycol ether, esters, ketones Alcohols, esters, ketones Water, alcohols Stabilization Dilution Precipitation* Dilution, Precipitation Additives (e.g. pigments) Properties Glass-like, brittle, heat resistant Scratch resistant, flexible Good adhesion on metals Application Temperature-resistant coatings Scratch resistant UV coatings Corrosion protection Sol-gel materials with shelf life between several months up to more than two years are obtained due to optimized production procedures *Worldwide patent W

6 x-protect products Binders and curing mechanism R H H H H H R R Si C N C C C N C Si R R H x H y H x R Lewis acids (AlH, ZrH ) Innovation: Direct water-free curing of high-molecular silanes is possible Activation temperature RT-80 C Acids / bases Activation temperature: > 100 C Resins and catalysts available from:

7 Product overview Corrosion protection for stainless steel, aluminium, zinc galvanized steel

8 High transparent corrosion protection Coil coating for aluminium coated uncoated Aluminium after 1000 h salt spray test - Anticorrosion coating for aluminium and highly polished aluminium - Coil coating application, PMT C, 1 min - Good adhesion without pretreatment - High transparency - Very good corrosion protection - Flexible, suitable for forming and punching

9 Protection for anodized aluminium Chemical resistant coatings Anodized aluminium part coated with 5 µm transparent x-protect coating after dipping in acidic (ph 1) and alkaline (ph 13.5) solution 15 min each at 40 C, against uncoated reference - Solvent and water based coatings based on sol-gel and SiliXan binders - Spray or dip coating - Thermal curing at 130 C - Good optical appearance - Abrasion resistant - Resistant against acidic (ph < 1) and alkaline cleaners (ph > 13)

10 Antifingerprint coating For brushed stainless steel Strong reduction of the visibility of fingerprints Prevention of the blue tarnishing of the stainless surface (corrosion/oxidation by salts and organic acids from finger sweat) Easy and remainderless removal of the fingerprints with a dry cloth Suited for structured surfaces (e.g. brushed), unsuited for high polished surfaces Very thin transparent coating ( µ) High abrasion resistance Good chemical resistance Conservation of the metal appearance No tarnish by fingerprints Keine Anlaufspuren durch Fingerprints metal Metallsubstrat substrate Invisible layer Unsichtbare Belegung von Metalloberflächen durch Nanopartikel of nanoparticles

11 Reference Reference for spray coating InoxPlus Sanitary equipment Spray cabinet with 4 spraying guns Stainless steel dishwasher panels Stainless steel outdoor lamps

12 Requirements for Coil Coating Coilcoating Blanking, cutting, lasing Forming by bending, deep-drawing or rolling Joining technology: Welding, brazing, gluing Finishing by brushing, grinding or polishing

13 Household appliances Forming and welding of stainless steel Exhaust hood ven Source: BSH Washing machine

14 Anti tarnish coatings Protection of stainless steel High temperature resistant coating for stainless steel Protection against tarnish (discoloration) at temperatures up to 600 C Transparent almost unaltered high-gloss appearance of stainless steel Application via dip-coating or spray-coating Crockmeter Test Cross Cut Test VP CA 1499 on stainless steel (AISI 304) Stainless steel after 1h at 600 C

15 Tarnish Protection Properties Flexibility of Coating After metal forming Heat treatment 1h at 500 C after forming Result: Good layer adhesion after forming process Very good tarnish protection also after forming Forming tool

16 Sealing for Zn and ZnNi Protection of zinc and zinc-nickel galvanized steel and cast iron parts - Water-based sealings for Zn and ZnNi galvanized parts - Spray or dip coating - Curing at 130 C - Resistant against acidic (ph < 1) and alkaline cleaners (ph > 13) ZnNi galvanized steel sheet with 2 µm sol-gel coating after 720 h neutral salt spray test (DIN EN IS 9227) against uncoated reference

17 Product overview x-tec and x-tec eco Active corrosion protection for steel and cast iron

18 Titanid Active Corrosion Protection Titanid principle Passivation of discrete metal pigments without loss of electric conductivity Combination of aluminium, magnesium or zinc pigments possible Nano Ti x coating on the pigment Cathodic corrosion protection for steel and significant reduction of white rust formation Al Ti x 5 µm Metal particles with Nano-Ti x passivation SEM cross section of Ti x -modified Al-particles, Ti x layer thickness approx nm

19 Titanid Active Corrosion Protection Uncoated (22MnB5) Electrogalvanized (7 µm Zn) on steel NXACP-Zn coating (22MnB5) in 7 µm Potential measurement of TITANID (Zn) on 22MnB5 in 3% NaCl solution E E [V] 0-0,1-0,2-0,3-0,4-0,5-0,6-0,7-0,8-0, t [h] t [h] 1000 h salt spray 125 h SST > h SST Constant potential of -0.8 V Titanid (Zn) on 22MnB5 steel compared to uncoated steel sheet and zinc-galvanized steel sheet with same coating thickness after salt spray test SST (IS 9227) - No corrosion on steel sheet after > h salt spray test - Considerably less white rust as compared to electrogalvanized or HDG - Electrochemical potential of -0.8 V proves cathodic corrosion protection

20 Titanid Active Corrosion Protection NXACP-Zn First Titanid serial product commercially available since September 2009 MULTI ZINC from Würth ( new product name PRMAX Room temperature curing zinc aerosol spray with cathodic corrosion protection More than 500 h salt spray test with µm coating thickness, worldwide unique performance Bright silvery appearance

21 Further applications Ideas for applications Corrosion protection for offshore wind power stations, industrial tubes, small parts like screws and bolts, cast iron parts,...

22 Water-based formulation x-tec eco Tailoring of sol-gel binders for anti corrosion coatings R R Si R R Hydrolysis + H 2 Tailoring of binders with links to - inorganic or metallic substrates H R Si H H condensation - H 2 surface modification H R Si R Si H H rganic crosslinking - fillers or functional particles, e.g. metals -> Development of a water based sol-gel binder Structuring by -particles - With good anticorrosion properties H - With low curing temperature - Suitable for bonding of metal Inorganic condensation pigments

23 Coating Formulation Basic optimization Formulation of coating materials consisting of a water based binder, zinc and aluminium pigments and additives ptimization of - Appearance - Low curing temperature - Corrosion protection - Processability - Pot life -> Products x-tec eco 4042 and x-tec eco 4047

24 Coating of different types of brake discs x-tec eco on brake discs Cast iron brake disc coated with x-tec eco 4042 Alternative brake disc types, lightweight construction disc partly coated High-grade appearance and homogeneous coating thickness by automatic spray coating process

25 Corrosion test Neutral salt spray test (NSS) according to DIN EN IS After 120 h NSS test After 300 h NSS test - No red rust after 120 h salt spray test - Up to > 400 h salt spray test possible on brake disc, more than 1000 h on steel sheet - Absolute resistance against rim cleaners by use of additional topcoat x-tec eco top!

26 x-tec eco black Zinc flake, water based, black x-tec eco black is a water based anticorrosion coating for brake discs with an attractive anthracite appearance. Properties: Curing temperature: Roomtemp C (RT-482 F) Temperature resistance: > 300 C (482 F) Coating thickness: 5 30 µm Salt spray test (DIN EN IS 9227): up to 500 h (depending on geometry and coating thickness) Application: Preferably spray coating. Dip and flow coating possible. Free from chromium Suitable for all functional surface areas including friction ring and flange

27 Salt spray test DIN EN IS 9227, 5% NaCl solution, 35 C x-tec eco black 480 h x-tec eco black after 480 h salt spray test on cast iron part

28 Linear taber with CS 17 friction pad, 550g load x-tec eco black x-tec eco black on cast iron, after 200 double strokes

29 Example of use Cast iron tubes State of the art anticorrosion coatings for pipelines: -2K polyurethane coating, 2-3 mm thickness -Epoxy coating µm thickness -two or three layer systems - No black water based active corrosion protection available before x-tec eco black

30 Thank You! NAN-X GmbH Saarbrücken NAN-X GmbH Theodor-Heuss-Str. 11a Saarbrücken GERMANY Phone +49 (0) Fax +49 (0) Web What can we do for you? Contact: Dr. Stefan Goedicke Phone +49 (0)