surface-fouling-affecting-finishing-and-assuranceSurface fouling also affects subsequent finishingsteps and quality assurance in damaging ways.Flaws on galvanic coatings due tooxides, grease, etc.- Insufficient coating thickness- Undesirable coating structure- Pores- Flaking, insufficient bond strength Flaws on coatings due tolacquers, on elastomers throughgrease, oil, etc.:- Insufficient bond strength- SeparationThermal spray coatings,flaws through oxide layers:- Bond strength/separationJoining processes such as soldering, diffusion welding, EBwelding, friction welding:- Lack of fusion- Pores- CrackingHydrogen absorption by titaniumalloys through iron deposits:- Embrittlement- Cracking- BreakoutsReactions, diffusion, LMEduring heat treatmentthrough coating powder, solder, metal wear products:- Embrittlement- CrackingReducing the sensitivityof penetrant testing through worsened wettability (silicon)Flaws in diffusion coatings throughdiffusion-preventing deposits suchas oxide coatingsWorsened macro etching asa process step (e.g. beforeelectroplating) and as quality assurance (segregationetching such as blue etchanodizing on Ti alloys orNi alloys)Stress corrosion cracking in titanium alloys when heated above 450 °C (welding,heat treatment), caused by residue containing Cl, such as fingerprints, thin reactionzones with Cl-based cleaning agents ("Tri", "Per") and etching media. Fouling DamageFinishing processDamage isnoticed