Questions and Answers
What is steel?
What TWO factors determine the behavior and properties of a particular metal?
Chemical composition, heat treatment
What does chemical composition refer to?
The combination of materials at the atomic level
What is heat treatment?
Signup and view all the answers
All steels contain ____ , ______.
Signup and view all the answers
What is Alloy Steel?
Signup and view all the answers
What is an Electric Arc Furnace?
Signup and view all the answers
What are the two key organizations that combined to create the classifications of steel?
Signup and view all the answers
What does AISI-SAE Designations refer to?
Signup and view all the answers
What is another common classification system for metals?
Signup and view all the answers
What are plain carbon steels?
Signup and view all the answers
Carbon steels account for over 75% of manufactured steel ______ ______.
Signup and view all the answers
What are impurities in metals?
Signup and view all the answers
Match the following groups with their carbon content:
Signup and view all the answers
What does hardenability refer to?
Signup and view all the answers
What characteristic do stainless steels have?
Signup and view all the answers
What defines Tool steels?
Signup and view all the answers
What element is used to add hardness and wear resistance to steel?
Signup and view all the answers
What are nonferrous metals?
Signup and view all the answers
How can nonferrous metals be classified?
Signup and view all the answers
Study Notes
Steel and Definition
- Steel is a metal alloy primarily composed of iron and carbon, often containing small amounts of manganese, phosphorus, sulfur, and silicon.
Metal Grades and Classification
- Grades refer to numerical designations that describe the content of metal alloys.
- Classification of metals helps to understand their specific properties and behaviors.
Factors Influencing Metal Properties
- The behavior and properties of metals are determined by:
- Chemical composition: The atomic-level makeup of the material.
- Heat treatment: A process of heating and cooling to change the metal's structure and properties.
Steel Composition
- All steel contains primarily iron and carbon.
- Alloy steel contains additional materials intentionally added to enhance specific properties.
Steel Production Process
- Electric arc furnaces utilize electric arcs between electrodes to transform pig iron and other materials into steel.
Organizations and Classification Systems
- The American Iron and Steel Institute (AISI) and the Society of Automotive Engineers (SAE) created the classifications for steel.
- AISI-SAE designations use a three- or four-number code to indicate the percentages of a steel's components.
- The Unified Numbering System (UNS) employs five numbers for classification and is not limited to steel.
Types of Carbon Steel
- Plain carbon steels contain less than 3% of elements other than iron and carbon, making them the most "pure" form.
- Carbon steels account for more than 75% of manufactured steel, with three main groups:
- Low-carbon steels: Contain less than 0.3% carbon.
- Medium-carbon steels: Contain between 0.3% and 0.5% carbon.
- High-carbon steels: Contain more than 0.5% carbon.
Carbon Steel Series
- Four series define different carbon steels:
- 10XX: No added elements.
- 11XX: Extra sulfur.
- 12XX: Extra sulfur and phosphorus.
- 15XX: Contains manganese in the range of 1.00-1.65%.
Steel Designations
- "E": Stands for steels produced in an electric arc furnace.
- "H": Indicates special hardenability properties of the metal.
- "B": Indicates the presence of boron.
- "L": Indicates the presence of lead.
Specialized Steel Types
- Stainless steels are characterized by more than 15% chromium and excellent corrosion resistance.
- Tool steels are designed for high wear resistance, toughness, and strength.
Additional Metal Types
- Chromium is used in ferrous alloys to enhance hardness and wear resistance; stainless steels contain significant amounts of chromium.
- Nonferrous metals are classified using the UNS and do not intentionally contain iron.
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
