Hi
Cant find any posts for the electro chemical coloring of stainless steel, the few people /makers I have spoken to here (South Africa) all go hmmmm thats a patented process etc
I found a scientific article which I cant quite understand, on the process and wondered if anyone could confirm that it will work or point me to a (free) process to do SS. I am quite capable of building the required PSU etc I just need to confirm, voltages currents etc as well as chemical mixtures etc.
A brief extract from the full artical named!
Chemical & Electrochemical Coloration of Stainless Steel and Pitting Corrosion Resistance Studies.
Acid Solution:
5.0 mol L-1 H2SO4 (I assume sulphuric acid)
2.5 mol L-1 Cr03 ( I assume Chromic acid Not sure how to mix)
Temp:
70 deg C (chemical immersion only)
25 deg C (chemical immersion and applied voltage/current)
Voltage & Current ( one of 2 ways):
1. DC Alternating 10sec pulses min 0.35 vdc max 0.75vdc
2. Triangular Current Scan 9mA per sec min -0.81mA max 2mA
Color Variation Achieved by time:
10mins 15 20 25 30 35 40 45 50mins
brown reddish brown gold blue greenish blue green reddish brown
It appears in the study they were able to color by just de greasing and immersion in acid over time as well as appling a voltage/current.
Does any of this make sense to anyone? I can find lost on titanium coloring but a lot of makes are coloring stainless steel this way, or am I wrong?
Jeff
Cant find any posts for the electro chemical coloring of stainless steel, the few people /makers I have spoken to here (South Africa) all go hmmmm thats a patented process etc
I found a scientific article which I cant quite understand, on the process and wondered if anyone could confirm that it will work or point me to a (free) process to do SS. I am quite capable of building the required PSU etc I just need to confirm, voltages currents etc as well as chemical mixtures etc.
A brief extract from the full artical named!
Chemical & Electrochemical Coloration of Stainless Steel and Pitting Corrosion Resistance Studies.
Acid Solution:
5.0 mol L-1 H2SO4 (I assume sulphuric acid)
2.5 mol L-1 Cr03 ( I assume Chromic acid Not sure how to mix)
Temp:
70 deg C (chemical immersion only)
25 deg C (chemical immersion and applied voltage/current)
Voltage & Current ( one of 2 ways):
1. DC Alternating 10sec pulses min 0.35 vdc max 0.75vdc
2. Triangular Current Scan 9mA per sec min -0.81mA max 2mA
Color Variation Achieved by time:
10mins 15 20 25 30 35 40 45 50mins
brown reddish brown gold blue greenish blue green reddish brown
It appears in the study they were able to color by just de greasing and immersion in acid over time as well as appling a voltage/current.
Does any of this make sense to anyone? I can find lost on titanium coloring but a lot of makes are coloring stainless steel this way, or am I wrong?
Jeff
