Table 6. Inorganic Coatings on Steels 



Alloy 



Exposure 

 (day) 



Depth 

 (ft) 



Paint Coating 



Condition 



After 

 Exposure" 



Source 



AISI 4130 



123 



5,640 



Wash primer, MIL-C-8541 



NPF 



NADC (7) 





403 



6,780 



Epoxy primer, MIL-P-23377 









1,064 



5,300 



Epoxy topcoat, MIL-C-22750 









197 



2,340 











402 



2,370 









AISI 4340 



197 



2,340 



Wash primer, MIL-C-8541 



NPF 



NADC (7) 





402 



2,370 



Epoxy primer, MIL-P-23377 

 Epoxy topcoat, MIL-C-22750 







18% Ni, maraging 



123 



5,640 



Wash primer, MIL-C-8541 



NPF 



NADC (7) 





403 



6,780 



Epoxy primer, MIL-P-23377 









197 



2,340 



Epoxy topcoat, MIL-C-22750 









402 



2,370 









HSLA No. 5 



197 



2,340 



Wash primer, MIL-C-8541 

 Epoxy primer, MIL-P-23377 

 Epoxy topcoat, MIL-C-22750 



NPF 



NADC (7) 



HSLA No. 4 



189 



5,900 



Zinc rich primer, 8 mils 



RS 



CEL (4) 



HSLA No. 5 



189 



5,900 



Zinc rich primer, 8 mils 



RS 



CEL (4) 



HSLA No. 13 



189 



5,900 



Zinc rich primer, 8 mils 



RS 



CEL (4) 



HSLA No. 4 



189 



5,900 



Wash primer, MIL-C-8514, 1 mil 



NPF 



CEL (4) 



HSLA No. 5 



189 



5,900 



Zinc rich primer, 8 mils 



NPF 



CEL (4) 



HSLA No. 13 



189 



5,900 



Epoxy topcoat, 6 mils 



NPF 



CEL (4) 



HSLA No. 4 



189 



5,900 



Epoxy tar primer, 8 mils 



NPF 



CEL (4) 



HSLA No. 5 



189 



5,900 



Epoxy tar topcoat, 8 mils 



NPF 



CEL (4) 



HSLA No. 1 3 



189 



5,900 





NPF 



CEL (4) 



HSLA No. 4 



189 



5,900 



Epoxy tar primer, 8 mils 



RS, IPF 



CEL (4) 



HSLA No. 5 



189 



5,900 



Epoxy tar topcoat, aluminum pigmented, 8 mils 



NPF 



CEL (4) 



HSLA No. 1 3 



189 



5,900 





NPF 



CEL (4) 



HSLA No. 3 



197 



2,340 



Epoxy primer, 162-Y-26, W.P. Fuller Co. 



GC 



Boeing (6) 



HSLA No. 6 



197 



2,340 



Topcoat, Epicote Finish 26-64, Unit 



GC 



Boeing (6) 



12% Ni, maraging 



197 



2,340 



Gull gray, National Lead Co. 



FPF 



Boeing (6) 



18% Ni, maraging 



197 



2,340 





FPF 



Boeing (6) 



D6AC 



197 



2,340 





GC 



Boeing (6) 



HSLA No. 3 



197 



2,340 



Polyurethane, laminar X500 



PC 



Boeing (6) 



HSLA No. 6 



197 



2,340 



Primer, 4-G-14, green 



PB 



Boeing (6) 



12% Ni, maraging 



197 



2,340 



Topcoat, 4-W-1A, white 



NPF 



Boeing (6) 



18% Ni, maraging 



197 



2,340 



Magna Coating and Chemical Co. 



FPF 



Boeing (6) 



D6AC 



197 



2,340 





GC 



Boeing (6) 



Symbols signify the following: 



GC = Good condition. 

 FPF = Few spots of paint failure. 

 IPF = Incipient paint failure. 

 NPF = No paint failure. 



PC = Paint cracked. 

 PB = Paint blistered. 

 RS = Rust stains. 



Numbers indicate references at end of report. 



33 



