Fighting wear, corrosion, galling and fatigue on stainless steel and - - PowerPoint PPT Presentation
Fighting wear, corrosion, galling and fatigue on stainless steel and titanium alloys Agenda 10.10.19 Expanite Introduction From Research to business Facts & Figures Strategy Key pointers Expanite processes. This is how we do it Wear and
Expanite Introduction From Research to business Facts & Figures Strategy Key pointers Expanite processes. This is how we do it Wear and Corrosion after… Testing Expanite ExpaniteHard-Ti
…but development goes back to 2000!
changer on the following parameters
University anno 2009 Hillerød ultimo 2012
hardening as strategically important to their business
Goes beyond the surface to reduce lead time and costs
Expanite patent N + C not able to penetrate oxide layer Expanite gas process removes oxide layer N + C is now able to enter material
Too high temperature – corrosion resistance lost!
Low temperature – supersaturated solid solution
Changing thermodynamical parameters
A technology = process/recipe = time + temperature + pressure + gas flow + surface physics & chemistry in a furnace = a gas-based diffusion process
N + C not able to penetrate
layer Expanite gas process removes
layer N + C is now able to enter material
150 250 350 450 550 650 750 850 950 1050 1150 50 100
Hardness [HV 0.01] Distance from surface [µm]
Micrographs & hardness profile of part in AISI316 ISO9227 168hr salt spray
Improving hardness and in the same time improving/restoring corrosion resistance beyond what the market previously has seen
Accurate control
Bulk-ware treatment
hardening
Identical temperature and time – only increasing gas potential
Temperature in vacuum: 1000-1200C Fast gas quench Adds nitrogen DK: 400x400x600 DE: 400x400x1000
Transgranular Cellular Grain Boundary Cr2N
c h
Nitrogen in solid solution
Transgranular Cellular Grain Boundary Cr2N
c h
ExpaniteHigh-T applies special gas quench for high interstitial contents High pressure N2 quench can impair the corrosion resistance!!
N2 cooling compromise corrosion resistance
Expanite patent
N2 cooling gas Not N2 cooling gas
Surface decorated with fine surface nitrides
Martensitic stainless steel
Hardness and corrosion resistance increase!
Duplex stainless steel
Austenite + ferrite Expanded austenite Carbon martensite Nitrogen martensite
350 400 450 500 550 600 650 700 750 0.4 0.8 1.2 1.6 2
Hardness [HV 0.3] Distance from surface [mm]
Treatment: ExpaniteHigh-T Case Depth High-T: 0.55 mm Surface hardness: 950 HV0.3 12.5Cr-0.12C-(1.5Mn+1.0Si max)
Temperature in atmospheric environment: 380-470C Adds nitrogen and carbon in solid solution DK: 600x600x1000 DE: 800x800x1000
1 2 3 4 5 6 20 40 60 80 100 120 140
Weight Loss [mg] Time [min]
Material loss
Untreated ExpaniteHighT SuperExpanite
Lubrication: none Ceramic silicon nitride ball Force: 25N Total sliding distance: 100m
°
Main conclusion: 125 times less wear on SuperExpanite treated plane surface
Non-treated 316 vs. 316 reference SuperExpanite vs. SuperExpanite
Non-treated Expanite-treated 0.5 ksi + no 1 ksi + no 2 ksi + no 5 ksi + no … … … 40 ksi + no
–Steven Budinski Owner/ Bud Labs
100 300 500 700 900 1100 1300 1500 1E-08 0.00000010.000001 0.00001 0.0001 0.001 0.01 0.1 1 10 100
AISI 316 Anne aled
* EN 1.4401 (AISI 316) Pitting resistance in seawater
SuperExpanite ExpaniteHigh-T Reference Pitting potential increase: 400mV
Voltage
Current
200 400 600 800 1000 1200 1E-08 0.0000001 0.000001 0.00001 0.0001 0.001 0.01 0.1 1 10 100
AISI 316 Annealed AISI 304 Annealed AISI 304 ExpaniteHighT V1
316 reference 304 reference 304 ExpaniteHigh-T
*EN 1.4401 / EN 1.4301 (AISI 316/304) Pitting resistance in seawater
Voltage Current
ExpaniteHard-Ti
back, buckle) from Swiss watch brand Horage
hardened by Expanite (ExpaniteHard-Ti); 30µm and approx. 1000HV.
Short process time Cleaner Bulk wear Cost effective Improving hardness and in the same time Improving/restoring corrosion resistance Improving wear, galling or corrosion