week 7 selection of ferrous material (1)

Hanafi,JKM,PPD,2015 1

En. Muhammad Hanafi Bin Asril Rajo Mantari

DAM 21102ENGINEERING MATERIALS SELECTION

SELECTION OF FERROUS MATERIALS

CONTENT1. Introduction2. Designation, Classification & specification for

Steel3. Procurement & Specification

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Introduction

Ferrous metals & alloys – irons with carbon added to them– Alloys < 2% C – STEEL– Alloys > 2% C – CAST IRON

Fe-C Phase Diagram

Cast Iron

Steel

Overview

Low-Carbon SteelsMedium-Carbon Steels High-Carbon Steels

Cast Irons Stainless Steels

Example of Product

Designation, Classification, and Specifications for Steels

• Designation:– American Society for Testing and Materials (ASTM) Standard E 527 –

The Unified Numbering System (UNS) of Metals and Alloys.

• Classification according to:– Composition– Strength– Product Shape, Finish Processing and Quality Descriptors

DesignationUNS of Nonferrous Metals & Alloys

• A00001 – A99999 : Al & Al alloys• C00001 – C99999 : Cu & Cu alloys• E00001 – E99999 : rare earth & rare earth like metals & alloys• L00001 – L99999 : low melting metals & alloys• M00001 – M99999 : misc. nonferrous metals & alloys• N00001 – N99999 : Ni & Ni alloys• P00001 – P99999 : precious metals & alloys• R00001 – R99999 : reactive & refractory metals & alloys• Z00001 – Z99999 : Zn & Zn alloys

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UNS of Ferrous Metals & Alloys• D00001 – D99999 : specified mechanical properties

steels• F00001 – F99999 : cast irons and cast steels• G00001 – G99999 : AISI and SAE carbon & alloy steels• H00001 – H99999 : AISI H-steels• J00001 – J99999 : cast steels (except tool steels)• K00001 – K99999 : misc. steels & ferrous alloys• S00001 – S99999 : heat & corr. Resistant (stainless)

steels• T00001 – T99999 : tool steels

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AISI-SAE vs ASTM vs ASME Designations

• ASTM designation is an arbitrarily chosen number prefixed by the letter “A”, which is designated for ferrous materials AXYZ

• ASTM designation are also adopted by ASME* and prefixed by letter “S” SAXYZ

• ASME = American Society for Mechanical Engineers

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Classification According to CompositionCarbon Content Alloy Content

Low Carbon: < 0.25%

Medium Carbon: 0.25 – 0.55%

High Carbon: > 0.55%

Tool steels and stainless steels

Plain Carbon – no alloying element except Mn up to 1.65%

Low Alloy – total alloy content < 5%

High Alloy – total alloy content > 5%

Classification According to Composition• Plain carbon and low alloy steels coded

according AISI – SAE* system• AISI – American Iron and Steel Institution• SAE – Society for Automotive Engineering

AISI-SAE system of designations for carbon and low alloy steels

Carbon Steels• 10XX or 10XXX– First two digits (10) – type of alloy addition– XX / XXX indicates % carbon when divided by

100– Eg: 1010 0.1% C; 10100 1%C– Exceptional for 9XX (SAE grades XX indicates

minimum yield strength in ksi)

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Classification According to Strength

• Start with properties of structural quality plain C steels with low yield strength generally < 40 ksi

• Common materials used for construction buildings, bridges and ships

• Low strength : < 40 ksi– Hot rolled

• High strength : 40 – 120 ksi– Up to 80 ksi Hot rolled with ferrite-pearlite or reduced pearlite

microstructures; Low alloy additions (HSLA) eg. SAE 9XX steels– Excess 80 ksi fine structure of lower bainite, and/or quenched and

tempered martensite • Ultra-high strength : min. 200 ksi

– All quenched and tempered medium carbon, low alloy steels or aged high-alloy steels and low-carbon maraging steels

– Used as aerospace and defense industry structural materials

ASTM Specifications for structural quality carbon steel platesSpec. Steel Type and conditionC SteelA36 Carbon steel plates, bars and shapes

A131 Carbon and HSLA steel plates, bars, shapes and rivets for ships

A283 Carbon steel plates of low or intermediate tensile strength

A284 C-Si steel plates of low or intermediate tensile strength for machine

parts & general construction

A440 C steel plates, bars & shapes of high tensile strength

A529 C steel plates, bars, shapes & sheet piling with 290 MPa (42 ksi) min. yield point

A573 C steel plates for applications requiring toughness at atmospheric temperature.

A678 Quenched and tempered C steel plates

A709 C, alloy & HSLA steel plates, bars & shapes for bridges

Classification According to Product Shape, Finish Processing and Quality Descriptors

• Product Shape– According to thickness and width

• “Bars” include– Round, square, hexagon and similar cross section 9.52

mm (⅜ in) and greater across– Small angels, channels, tees and other standard

shapes less than 76 mm (3 in) across– Concrete-reinforcing bars

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Product classification of flat-rolled carbon and low-alloy steels according to size, width and thickness

Thickness (in)

Specified Width (in)

To 3.5 More than 3.5 to 6

More than 6 to 8

More than 8 to 12

More than 12 to 28

More than 48

0.230 and above0.229 – 0.2040.203 – 0.1800.179 and below

Bara

Bara

StripStrip

Bara

Bara

StripStrip

Bara

StripStripStrip

Platea

StripStripStrip

Platea

SheetSheetSheet

Platea

Platea

Platea

Sheetb

a Subject to certain conditions, these dimensions are sold as carbon sheet or strip as well as bars or plate

b These products classifications for hot-rolled sheet are based on the median point of the minimum thickness ordered plus full published thickness tolerances

Classification According to Product Shape, Finish Processing and Quality Descriptors

• Finish processing:– Signify the last processing the steel has undergone

– hot-rolled, cold-rolled, annealed, hot-dip galvanizing etc.

• Quality descriptors– Indicate product suitability for certain applications

or fabrication processes

• Quality Descriptors Certain mechanical and physical attributes of products due to:– Degree of internal soundness– Relative uniformity of chemical compositions– Relative freedom from surface imperfections– Relative size of discard cropped from ingot– Extensive testing during manufacturing– Number, size, shape and distribution of nonmetallic

inclusions (ie. Cleanness or inclusion rating of steel)– Relative hardenability requirements

Classification According to Product Shape, Finish Processing and Quality Descriptors

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Procurement & Specifications

• Procurement– A materials procurer usually writes a summary of

the company’s need to the material supplier or vendor by writing a specification

• Specification– Written document of the technical and other

requirement that a product must meet

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Procurement & Specifications• Adequate specification contains:

– SCOPE• Classification (size, condition, processing)

– CHEMICAL COMPOSITION• Well-recognize designation or specification

– QUALITY• Quality descriptors

– QUANTITATIVE• Composition, physical/mechanical properties range

– OTHER REQUIREMENTS• Special tolerances, surface preparation, edge & finish on flat rolled

products etc.

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Procurement & Specification

• ASTM codes specifications

• AISI-SAE designation part of spec.

• Terms (interchangeably):– Grade

• Chemical composition– Type

• deoxidation practice (killed, semikilled or rimmed)– Class

• Other attributes (ie strength, surface finish)

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Carbon & Low-AlloyStructural Steel

• Low carbon low alloy steel & low plain carbon steel used for civil engineering structures

• Alloy addition in low carbon low alloy steel to increase corrosion resistance or strength

• In various form (eg. bars, plates, strips) construction industries

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Plain high carbon

High carbon low alloy Steel

Cutting Tool High strength low alloy (HSLA)

Low carbon low alloy steel

Plain low carbon

Medium carbon low alloy Steel

Plain medium carbon

Heat treatable

Hanafi,JKM,PPD,2015 30

......FINISH ......THank you