Nontraditional Machining Operations Review Questions

Question 1

Why are the nontraditional material removal processes important?

Answer 1

• Machine materials that have special properties that make them difficult or impossible to machine by conventional methods
• Need for unusual and complex geometries that cannot be accomplished by conventional machining
• Need to avoid surface damage that can accompany stresses created by conventional machining

Question 2

There are four categories of nontraditional machining processes, based on principal energy form. Name four categories

Answer 2

• Mechanical
• Electrical
• Thermal
• Chemical

Question 3

How does ultrasonic machining process work?

Answer 3

Abrasives contained in a slurry are driven at high velocity against the work by a tool vibrating at low amplitude and high frequency

Tool oscillates in a diection perpendicular to work surface, and fed slowly into work, so that shape of tool is formed in part

Question 4

Describe water jet cutting process

Answer 4

Uses fine high pressure, high velocity stream of water at the surface to cause cutting of the work

Question 5

What is the difference between water jet cutting, abrasive water jet cutting, and abrasive jet cutting?

Answer 5

Abrasive water jet cutting is used when Water Jet Cutting is used on metal parts.

Introduces abrasive particles into the stream.

Question 6

Name the three main types of electrochemical machining

Answer 6

• Electrochemical deburring
• Electrochemical machining
• Electrochemical grinding

Question 7

Identify the two significant disadvantages of electrochemical machining

Answer 7

• significant cost of electrical power to drive operation
• problems disposing of electrolyte sludge

Question 8

How does increasing discharge current affect metal removal rate and surface finish in electric discharge machining?

Answer 8

metal removal rate increases

surface finish is bst obtained at low discharge current

Question 9

What is meant by the term overcut in electric discharge machining?

Answer 9

Distance by which the machined cavity in the workpart exceeds the size of the tool on each side

Produced because the electrical discharges occur at the sides of the tool as well as its frontal area

Question 10

Name the four principal steps in chemical machining

Answer 10

1. cleaning
2. masking
3. etching
4. demasking

Question 11

What are the three methods of performing the masking step in chemical machining?

Answer 11

• photographic resist method
• screen resist method
• cut and peel method

Question 12

What is photoresist in chemical machining

Answer 12

photographic resist method

Uses photographic techniques to perform the masking step