Chapter 2 Flashcards Preview

introduction to Manufacturing Processes > Chapter 2 > Flashcards

Flashcards in Chapter 2 Deck (28):
1

Types of ferrous and nonferrous

Ferrous - Steel and cast iron

Nonferrous - aluminum and copper

2

Four types of steel

Plain carbon steel
Low alloy steel
Stainless Steels
Tool Steels

3

Plain carbon steel. Explain strength and ductility.

Mainly carbon. Strength increases with carbon but ductility decreases. Heat treated will make martensite which is very strong and hard.

4

Plain carbon steel. Explain use of low, medium, and high carbon steel.

Low carbon (<0.20%) - railroad rails
Medium carbon (0.20% to 0.50%) - Machinery components.
High Carbon (>0.50%) - Springs, and cutting tools and blades

5

Low alloy steel

Superior to plain carbon steel after heat treatment. High strength, hardness, hot hardness,

6

Stainless Steel

15% Chromium. Nickel protects against corrosion. Carbon adds strength and hardness but reduces corrosion protection.

More expensive than low alloy and plain C.

7

Tool steels

Highly alloyed. Heat treated. For dies and molds.

8

Properties of Nickel and alloys

Magnetic. Modulus of E close to iron. Superior when heat treated. Very corrosive resistant.

9

Properties of Zinc and alloys

Low melting temp so for die casting. Corrosion protection as coating.

10

Properties of Superalloys

Resist surface degradation at high temperature. Very expensive. Gas turbines
Meant for 1100 C temp.

11

What are new Ceramics

Controlled simple structures.
oxides, carbides, nitrides, and borides.

12

Oxides ceramics. Properties

Al2O3 or Alumina.

Good hot hardness, low thermal conductivity, and good corrosive resistance

13

Carbide ceramics

Silicon Carbide and tungsten carbide

Cutting tools

14

Properties of Nitrides

Silicon nitride and boron nitride
Hard, brittle, high melting temperature, electrically insulating.

Gas turbine components and cutting tool coatings

15

Glass properties

State of matter - Not enough time to cool from molten state to crystalline structure.

Type of ceramic - Inorganic nonmetallic that cools to a rigid condition without crystallizing.

16

Main component of Glass

SiO2. Silica. 50% to 70%
Naturally transforms into a glassy state when cooling instead of crystallization like other ceramics.

17

Why add ingredients to glass

Adds color, acts as flux (promotes fusion), alter index of refraction for optics, and decreases viscosity

18

Polymer and properties

Organic long-chain molecules.
Low density. good strength to weight. high corrosion resistance. low electrical and thermal conductivity.

19

Types of Polymers

Plastics - thermosetting and thermoplastic
Rubber - elastomers

20

Thermoplastics

Polyethylene and nylon. Solid at ambient temp but liquid at ~100 degrees. No degradation after cycles of cooling and heating.

21

Thermosettings

Phenolics and epoxies. Degrades (char) after repeated heating cycles. When heated they flow and shape around mold. Elevated temp cause chemical reaction making it in-fusible.

22

Elastomers

Rubbers. Extreme elastic extensibility (factor of 10) under relatively low mechanical stress.

Similar structures to thermosets but different properties. Both different to thermoplastics.

23

Importance of Polymers. 4 traits.

Net shape processing.
Cost competitive.
Require less energy to produce than metals.
Transparency competes with glass.

24

Name polymer molecular structure

Linear (chain link), Branched (chain link but with branches), cross-linked (elastomers are loose; thermosets are tight)

25

Composite properties

Very strong and stiff yet light in weight.
Large toughness
Great fatigue properties

26

What are primary and secondary phases

Primary - The matrix when the secondary phase is embedded
Secondary - Reinforcing phase that reinforces the primary phase.

27

Reinforcing agent

It strengthens the material which as a fibers, particles or flakes.

28

Downsides to Polymers

Low strength
Low modulus of elasticity or stiffness
Service temperature range limited to a few hundred degrees
Degrade due to sunlight and other forms of radiation