Chapter 35 Flashcards
Lesser known joining processes?
Shrink fits, slots, and tabs.
Welding
Permanent joining of two materials
Coalescence
Welding is usually met by this. This is an induced combination of temperature, pressure, and metallurgical conditions.
Idea metallurgical bind:
Smooth surfaces, surfaces that are clean, and the joining of crystals with identical structures.
Cleaning metal surfaces in fusion welding?
The molten material and high temperature accelerated factions and contaminated are removed through fluxing agents. No new contaminâtes can be formed.
Heating and cooling
Change metal structure
To produce weld
Need a source of heat, a means of cleaning the metals, and caution to avoid harmful metallurgical effects.
American welding society
Uses letter symbols to classify various welding processes
Thermal cutting
Cutting metal sheets with welding
Weld metal properties
Can be changed by solutions of the filler, vaporization of alloys and gas metal reactions
Weld defects
Incomplete fusion, incomplete penetration
Incomplete penetration
Undesirable metallurgical changes: aging, grain growth, or transformations
Four basic types of fusion welds:
Bead weld, groove weld, fillet weld, and plug weld
Bead welds
Require no edge preparation. Used for joining thin sheets.
Grooved welds
Used for full thickness. Some form of edge preparation is required. V, double v, and J configurations are most commonly done with oxy flame cutting
