ME 151 19/20/28 (quizes)

Which of the following are typical advantages of nontraditional machining processes? (Select all that apply)

- Able to machine brittle, strong, and hard materials -Little to no residual stresses -Able to machine with very tight tolerances - Able to create complex or delicate geometry

Which of the following methods are used to create free-machining metals (in order to reduce the friction generated during cutting)? (Select all that apply)

- Adding alloying agents that serve as lubricants (such as lead) - Adding alloying agents that produce smaller cutting chips

Which of the following are typically considered to be disadvantages of additive processes? (Select all that apply)

- Difficult to make large parts - Slow production rates per part - Poor surface finish - Poor dimensional accuracy

Which of the following are functions of the dielectric fluid in Electrical Discharge Machining?

- electrical insulator - flushing away debris - coolant -local spark conductor

Which of the following are disadvantages of Electrochemical Machining? (Select all that apply

-Difficult to create sharp corners -Expensive tooling - Environmentally harmful by-products

Which of the following processes use rewritable photomasks? (select all that apply)

-Solid Ground Curing -Sintermask

Which of the following are typically considered to be major disadvantages of the Fused Deposition Modeling process? (Select all that apply)

-high material cost -relatively long build times -limited to low strength materials

The Electron Beam used in Electron Beam Melting has _____ power than the laser used in Selective Laser Sintering (SLS), producing_______ mechanical properties, but ______ surface finish than SLS.

-higher -better -worse

Assuming the descending platform (elevator platform) has just been moved down, place the following steps of the Solid Ground Curing process in the order in which they would occur.

1. A thin layer of uncured liquid is applied 2. Exposed to UV 3. Excess uncured liquid removed 4. Layer of liquid wax is added and solidified 5. Milling operation performed

For a material and etchant combination that has an Etch Factor of 1.7, if a trench 1mm deep was created and the original mask opening was 10mm wide, what would the total width of the final trench be? Provide the numerical answer only (in millimeters); do not include the units.

13.4

Abrasive particles used in many non-traditional mechanical machining processes are usually made of which type of material?

Ceramics

_________ is the term for self-excited vibration during machining; it causes distinct unwanted lines on the cut surface of the machined part.

Chatter

Which of these nontraditional machining methods is commonly used in the making of circuit boards?

Chemical Machining

The four basic physical components of any machining process are: the machining center, the workpiece, the workholding device and the ___________.

Cutting Tool

There are three major categories of vibration in machining; the amplitude of free vibrations tend to________with time, the amplitude of forced vibrations tend to _________with time, and the amplitude of self-excited vibrations tend to ________ with time.

Decrease Stay the same Increase

Continuous chips are the most desirable type during machining because they minimize tool wear and friction.

False

Machining is rarely used in the modern manufacturing of most products

False

Powder-based processes are typically considered to be the most wasteful of the additive manufacturing methods.

False

The majority of the power put into machining processes is converted into shear and sound.

False

The primary difference between Abrasive Waterjet Cutting (AWC) and Abrasive Jet Cutting (AJC) is the type of abrasive particles used in the process.

False

The ________ is defined as the amount of material removed per revolution or per pass of the tool over the workpiece.

Feed Rate

The poor surface finish in products produced using Selective Laser Sintering or Electron Beam Sintering is caused by:

High porosity in the sintered material

Which of the following methods is used to pattern live cells during organ printing?

Inkjet deposition

Which of the following is considered to be a major disadvantage of Laminated Object Manufacturing?

Large amount of material waste

The _____________ is the volume of material removed over time in a machining process.

Material Removal Rate

Electron Beam Machining, Ion Beam Machining, Laser Machining, and Plasma Arc Cutting are all thermal machining processes that rely on a focused beam of energy to locally melt or vaporize material on a workpiece.

True

One of the advantages of chemical machining is that it can be used to machine very large surfaces simultaneously.

True

The first additive process was invented in the 1980's and was limited to creating parts from a brittle photocurable polymer.

True

The main difference between Electrochemical Machining and Electrical Discharge Machining (EDM) is that in Electrochemical Machining, electricity is used to produce a chemical (etching) reaction, but in EDM electricity is used to produce a thermal (vaporization/melting) reaction.

True

The seven basic mechanical machining or "chip formation" processes are: turning, _________, drilling, shaping/planing, sawing, grinding and broaching.

milling