Supplementary Processing Elements

Braze procedure

1. Cleaning

• Chemical
• Mechanical
• Nickel plate
• Furnace clean
• Hydrogen fluoride

2. Assembly

•  Placement weld
• Tack
• Spot
• Resistance
• Fixturing

3. Alloy application

• Cements
• Product of the paint industry
• Temporary binder
• Poly isobutylene
• Acryloid
• Polyvinyl / gum / cellulose / parahydroxybenzonate

• Burns off at 480 °C (900 °F)

• Pastes
• Product of the food industry
• Long term powder suspension
• Burns off at 480 °C (900 °F)
• Water soluble or organic base 
• Product of the food industr
• Long term powder suspension
• Burns off at 480 °C (900 °F)
• Water soluble or organic base

4. Stop-off application 

• Deterrent to flow
• Ceramic plus vehicle
• Alumina
• Calcium carbonate
• Titania
• Boron nitride
• Poly isobutylene
• Lacquer

5. Thermal cycle 

• Furnace bake-out
• Thermocouple / temperature measurement 
• Preheat
• Braze time / temperature
• Cool down

6. Post treatment

• Thermal
• Chemical cleaning
• Mechanical cleaning
• Mechanical dimensioning

7. Inspection

• Non-destructive
• Visual
• X-ray
• Ultrasonic
• Liquid penetrant (ultraviolet)

• Destructive
• Tensile
• Hardness
• Metallography