Overview of Common Finishes

Common Finishes
ProductDiametersElectroplate zincColourDe-EmbrittleOrganicColourZinc FlakeColour
Nuts and Screws = < Grade 8 or 8.8  (Below 320 Hv or 1000Nmm2 )M1 - M5YESClearNO    
Bleached
Black
Colour
Olive Drab
M6 - M39YESClearNOYESCustomer to specifyYESSilver or black
Bleached
Black
Colour
Olive Drab
Nuts and Screws = > Grade 8 or 8.8 (Above 320 Hv or 1000Nmm2)M1 - M5YESClearYES    
Bleached
Black
Colour
Olive Drab
M6 - M39YESClearYESYESCustomer to specifyYESSilver or black
Bleached
Black
Colour
Olive Drab
Case Hardened FastenersM1 - M5YESClearYES    
Bleached
Black
Colour
Olive Drab
M6 - M39YESClearYESYESCustomer to specifyYESSilver or black
Bleached
Black
Colour
Olive Drab
Washers < = 320 Hv1mm - 39mmYESClearNO    
Bleached
Black
Colour
Olive Drab
Washers > = 320 Hv1mm - 39mmYESClearYES    
Bleached
Black
Colour
Olive Drab
 
Guide to Salt Spray Resistance  (According to BS 7371)
Electro Zinc Thread Diameter M1 - M2    =  3 microns
Clear                             White Corrosion  2 Hrs                 Red Rust  12 Hrs
Bleached                                 White Corrosion  6 Hrs Red Rust  12 Hrs
Colour                    White Corrosion  24 Hrs             Red Rust  24 Hrs
Olive Drab                           White Corrosion  24 HrsRed Rust  24 Hrs
Thread Diameter M2.5 - M5      = 5 microns
Clear                           White Corrosion  6 Hrs                 Red Rust  24 Hrs
Bleached                               White Corrosion  12 HrsRed Rust  36 Hrs
Colour                       White Corrosion  48 Hrs             Red Rust  72 Hrs
Black                                         White Corrosion  12 HrsRed Rust  36 Hrs
Olive Drab                           White Corrosion  72 HrsRed Rust  96 Hrs
Thread Diameter M6 - M10    = 8 microns
Clear                                             White Corrosion  6 HrsRed Rust  48 Hrs
Bleached                             White Corrosion  24 HrsRed Rust  72 Hrs
Black                           White Corrosion  24 Hrs             Red Rust  72 Hrs
Colour                       White Corrosion  72 Hrs             Red Rust  120 Hrs
Olive Drab             White Corrosion  96 Hrs             Red Rust  144 Hrs
Thread Diameter M12 - M20    = 12 Microns
Clear                                             White Corrosion  6 HrsRed Rust  72 Hrs
Black                                     White Corrosion  24 Hrs   Red Rust  96 Hrs
Bleached                 White Corrosion  24 Hrs           Red Rust  96 Hrs
Colour                                     White Corrosion  72 HrsRed Rust  144 Hrs
Olive Drab                         White Corrosion  96 HrsRed Rust  168 Hrs
Organic Minimum Thread Diameter M6
Type A72 Hrs
Type B120 Hrs
Type C192 Hrs
Type D240 Hrs
Zinc Flake Minimum Thread Diameter M6
Type A240 Hrs
Type B480Hrs

Notes  

As a result of the new EoLD, new Trivalent finishes have been developed which can improve corrosion resistance. Some of these can now achieve up to 1000 Hrs to Red Rust. For more details contact us.  

Adding Sealer to Electro Zinc finish will enhance performance (Excluding Olive Drab)  Unthreaded components - please refer to ISO 12329

Note: Due to the fact that fastening applications differ greatly, the above information is for guidance only and is correct to the best of our knowledge. The customer must satisfy themselves with the performance of the fastener and validity of the data. TR Fastenings will not be held responsible for any failure that may occur from the use of this information.