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What is the basic equation for calculating the MRR of a machining process?

MRR = (Removed Volume)/(Cutting Time)


What is adhesive wear?

Adhesive wear is incurred when a tangible force is applied and causes a shearing force between two contacted surfaces. Growth forms on the tool as a result.


Name three advantages of additive manufacturing.

-Waste is reduced/removed
-Multi-material objects are possible
-Energy is used more efficiently


Name two disadvantages of additive manufacturing.

-Production rate is very slow and expensive.
-Strength in z axis can be limited.


What is dot spacing in AM?

The distance between dot centers in inkjet printing.


What is the "Two Solvent System".

It is a solution to coffee staining. You mix two solvents of different boiling points together.


What is Brazing?

A joining process in which a filler metal is placed at or in between two surfaces to be joined.


In brazing. What is the relationship between lap distance and metal thickness.

Lap Distance = 1.25 * Metal Thickness


Name three advantages of Brazing.

-It can join different types of metals (ferrous to non-ferrous for example)
-Less heating is required as compared to welding. So it is quicker/more economical with a lower HAZ.
-Virtually all materials can be joined by some sort of brazing metal


Name two disadvantages of Brazing.

-Subsequent heating of the assembly can cause the filler metal to melt - destroying the joint.
-Brazed joints fail when heat is applied to repair damaged assemblies.


What is Resistance Welding?

The heat required for welding is produced by electrical resistance across the two components to be joined.


What is the sequence of resistance welding?

1-Apply pressure
2-Turn on current
3-Turn off current, keep pressure on
4-Release pressure, leaving weld nugget


Name the advantages, disadvantages and applications of resistance welding.

Advantages: No consumable electrodes, shielding gases or flux needed. It is easy and fast.
-Disadvantages: The equipment is complex and expensive
-Applications: Sheet metal fabrication and automotive body assembly


What is Cold Welding?

Metals are joined by the application of pressure to the work-piece via dies or roles. You have a cladding metal and a base metal.


In cold welding, what properties do the two metals need for the best bond.

The best bond is obtained with two similar metals.


Name an application of cold welding.

Welding wire stock (splicing wires together).


In Ultrasonic Welding, what forces are the two components subject to?

-A static normal force.
-An oscillating shearing (tangential) force


What does the shearing stress in ultrasonic welding cause?

Plastic deformation at the interface of the two components.


True or false. Melting/fusion occurs in ultrasonic welding.

FALSE. Neither occur.


What temperatures (think fraction) occur in the weld zone in ultrasonic welding?

The temperatures generated in the weld zone are usually 1/3 to 1/2 of the melting point of the joined metals.


What are three advantages of ultrasonic welding?

-It is versatile and reliable
-It can be used with non-metallic materials (like plastics)
-It can be used with dissimilar metallic work-pieces


What other process is friction welding technically known as? Why?

A forging process. Because plastic deformation occurs.


What are the advantages of friction welding?

-No consumable electrodes, shielding gases or flux are needed.
-It can join a variety of materials


What is the kerf?

The width of a cut made by a saw


How does Explosive Welding work?

Pressure is applied by detonating an explosive layer placed over one of the two components. It is detonated in a progressive fashion.


What causes the wavy interface in explosive welding?

The kinetic energy of the plate striking the mating component.


Name the advantages of explosive welding.

-The bond strength is high.
-The ability to join many combinations of different metals


Name an application of explosive welding.

Corrosion-resistant claddings on mild steel structures.


What is mechanical alloying and why is it used?

Powders of multiple metals are combined in a ball mill. The powders fracture and mix to form allow powders. It can give your final product specific mechanical properties.


What is communition?

You crush, mill or grind your metal to get a powder. It uses a hollow cylinder with large metal balls.