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来自: 中国湖北武汉
Steel
& b, @2 {) K4 Z( T% dClass Notes and lecture material
; z% l- Y3 J" B1 i; aFor4 W ?% C& T" k: m: j: S3 f+ b
MSE 651.01--
# X+ C2 N( ^, _& `/ Z ?9 kPhysical Metallurgy of Steel, H1 z- j5 x9 X' I
Notes compiled by: Glyn Meyrick, Professor Emeritus% p$ m5 V: {( i+ U* m/ O
Notes revised by: Robert H. Wagoner, Distinguished7 `9 U: Q' X* O% Q- L
Professor of Engineering& T" S6 o- J' V& W4 K0 F e
Web installation by: Wei Gan, Graduate Research Associate
; @6 w& }- C8 I# m, |/ CLast revision date: 1/8/01
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2 {' ` v- D! Y6 x) D- a2 jSTEEL: i/ [( P' Z) l2 \- V3 s# z9 i
Foreword; |- t* ~( C$ u% q6 x( e0 D+ ]
This document is intended to augment formal lectures on the general topic of the physical b$ T+ v3 z# l$ [4 r! ]" z
metallurgy of steels, presented within the MSE Department during the Fall Quarter, 1998. It is
' s G$ n7 @; x1 t5 w' [) Cbased on a variety of texts and published articles and also on personal experience. Specific. O! B% w+ }; K/ D9 x. p
references to sources are made within the document. However, the material is often in the form of# p( |# b( J* h0 a2 C
knowledge that has been accumulated by the work of many people and is "well-known" by experts# v+ T) H s3 Q' `. ~% q: @' k8 B
in the field. A detailed acknowledgment of the work of each contributor to the field is not attempted: k1 P: R" m4 v. X7 B
because that would be an awesome task. This document is not intended for publication and is
; K# R4 V R: }: ~restricted for use in MSE 651.01.
! x0 z5 B) X: _- R6 fTexts: Steels; Microstructures and Properties by R.W.K. Honeycombe (Edward Arnold)& Z1 S; ^. r3 }5 J& t
Principles of the Heat Treatment of Steel by G. Krauss (ASM)
& m: z$ j/ u9 m5 i+ pThe Physical Metallurgy of Steel by W.C. Leslie (McGraw Hill)
u L! ?4 V, F3 `/ A) z- cThe ASM Metal Handbooks.2 J2 R$ U) Z6 Y+ M! Z
Handbook of Stainless Steels, Peckner and Bernstein (eds.) McGraw Hill 1977
' `( Y, H# W4 cTool Steels Roberts and Cary, Edition 4, ASM, 1980
. b" S" z4 R6 G7 ~ YFerrous Physical Metallurgy A. K. Sinha, Butterworths 1989. P3 W1 i# ^" j
Introduction
7 Y+ [% I: J+ O$ i# eSteel is a family of materials that is derived from ores that are rich in iron, abundant in the
! Z3 t2 P3 z" V5 j1 l: \Earth’s crust and which are easily reduced by hot carbon to yield iron. Steels are very versatile; they
( \3 i1 m1 n( `: K+ ~/ H. t2 jcan be formed into desired shapes by plastic deformation produced by processes such as rolling( ]5 a: o' X' e( _4 P7 I" }
and forging; they can be treated to give them a wide range of mechanical properties which enable
6 G3 e" u9 E! J/ p z2 x5 d' cthem to be used for an enormous number of applications. Indeed, steel is ubiquitous in applications; ~0 S) _0 {" C3 Z; p
that directly affect the quality of our lives. Steel and cement constitute about 90% of the structural
" w% e( O5 ]5 Y; @" Dmaterials that are manufactured# J2 F. u6 X" ^4 d4 J
( Westwood, Met and Mat Trans, Vol. 27 A, June 1996, 1413).# c/ J/ I2 X/ `, F+ `
What, then, is steel?
" A: e) a0 Z; W; aA precise and concise definition of steel is not an easy thing to present because of the very# `" h: _5 ~& E; Z& P
large variety of alloys that bear the name. All of them, however, contain iron. We might reasonably- W1 I8 o6 [, n" Q7 F. s
begin by describing a steel as an alloy which contains iron as the major component. This is only a
/ T" }2 q( e$ wbeginning because there are alloys in which iron is the major constituent, that are not called steels;
: Z" L u5 n4 W3 N1 b; tfor example, cast irons and some superalloys. The major difference between a cast iron and a steel( l) K( b7 P; v2 |# Z
is that their carbon contents lie in two different ranges. These ranges are determined by the
" G A: h# S. L+ u; Dmaximum amount of carbon that can be dissolved into solid iron. This is approximately 2% by
2 I: r; ?! v' A2 Aweight (in FCC iron at 1146 °C). Steels are alloys that contain less than 2% carbon. Cast irons
5 x, }/ ?# m% z Kcontain more than 2 % carbon. Many steels contain specified minimum amounts of carbon. This
/ C5 L: u3 q" B9 Gdoes not mean that all steels must contain substantial quantities of carbon; in some steels the6 e; T, I, C! B P
carbon content is deliberately made very small and, also, the amount actually in solution is reduced- |# J# m+ ^ J/ Z
further by the addition of alloying elements that have a strong tendency to combine with the carbon' I+ }1 Z- G% O1 F- |/ e+ E
to form carbides.
0 U* r4 G/ s! N2 ^& b. I5 |Steels can be divided into two main groups; plain carbon steels and alloy steels. The latter* s3 k' l1 z& C5 M* |- ^
can then be subdivided into many groups according to chemistry ( e.g. standard low alloy steels),3 X/ i, _# o: b; ~3 j8 s
applications (e.g. tool steels ) or particular properties (e.g. stainless steels) etc. Let us begin with' @/ e+ ~1 K G- i! Z: F' |; J: d
22
! L3 d* z2 P/ i" C/ Xplain carbon steels; this group is the simplest to understand and it comprises steels that are used in6 @5 `4 ?& \3 E# a% H; q5 w
the greatest tonnage |
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