|
|

楼主 |
发表于 2011-3-6 17:40:02
|
显示全部楼层
来自: 中国湖北武汉
Steel
* ^9 R% d, I& _( y5 K# s7 D2 dClass Notes and lecture material0 |7 i6 X5 C T1 K
For
9 L c# G/ a. h* B, HMSE 651.01--
! I9 U, ^6 x/ t! r$ i9 @2 oPhysical Metallurgy of Steel7 ]* x) g0 G7 M
Notes compiled by: Glyn Meyrick, Professor Emeritus4 m9 X/ F+ W! E# A: a8 m
Notes revised by: Robert H. Wagoner, Distinguished% i, D- W- B* a! ~
Professor of Engineering, \1 ~6 N( C+ ~+ {
Web installation by: Wei Gan, Graduate Research Associate$ V, S$ C& @% R- j+ U9 Z" l- V: T' K
Last revision date: 1/8/01' y* ]( [; ?: g4 z0 }$ q+ Z/ |
11
; ~, o5 S7 p0 f1 _, Z# O+ xSTEEL) Z' x1 t" z3 o" \* _$ j+ `+ N$ D, u8 W! v
Foreword/ k- C: j" Z* } E9 B2 R8 X
This document is intended to augment formal lectures on the general topic of the physical7 L! _4 B; t3 ^7 C
metallurgy of steels, presented within the MSE Department during the Fall Quarter, 1998. It is) F0 B0 F# B3 G B: y. H' \
based on a variety of texts and published articles and also on personal experience. Specific
8 w# l! c2 q F+ p& yreferences to sources are made within the document. However, the material is often in the form of2 E. W" ^, a7 q1 J
knowledge that has been accumulated by the work of many people and is "well-known" by experts- t; l$ x/ d' j- x
in the field. A detailed acknowledgment of the work of each contributor to the field is not attempted
d; l4 a& @2 A: ^: R9 ^because that would be an awesome task. This document is not intended for publication and is
. P! k0 h; R) j9 g F, drestricted for use in MSE 651.01.
9 f) h# p, I _5 P$ ^* mTexts: Steels; Microstructures and Properties by R.W.K. Honeycombe (Edward Arnold)
; n* N2 }9 K6 o6 ?1 D% v0 m- JPrinciples of the Heat Treatment of Steel by G. Krauss (ASM)
- B6 n/ D6 e/ o( J5 J' lThe Physical Metallurgy of Steel by W.C. Leslie (McGraw Hill)
' v" h$ w* g) j( |5 D6 k5 T8 R: ZThe ASM Metal Handbooks.
8 q! e" ?; B3 O, T5 P+ `Handbook of Stainless Steels, Peckner and Bernstein (eds.) McGraw Hill 19779 n$ T, x/ ~+ K* F
Tool Steels Roberts and Cary, Edition 4, ASM, 1980# D. I& ?* R" Q5 z7 h7 }- P8 ?
Ferrous Physical Metallurgy A. K. Sinha, Butterworths 1989.( Z7 Z/ {8 j8 H* J" L+ ^2 _
Introduction
5 Q8 ~& f3 |, ], V/ h$ ESteel is a family of materials that is derived from ores that are rich in iron, abundant in the
2 A6 u; r' y" |# O, `6 nEarth’s crust and which are easily reduced by hot carbon to yield iron. Steels are very versatile; they
" B D$ z( J% q% ican be formed into desired shapes by plastic deformation produced by processes such as rolling% \0 b6 g9 v4 A/ a3 D/ t- ?
and forging; they can be treated to give them a wide range of mechanical properties which enable& o' L4 d% N! Z K( y. H, _' m' ?
them to be used for an enormous number of applications. Indeed, steel is ubiquitous in applications
1 V( h! D0 u9 r4 A3 n% jthat directly affect the quality of our lives. Steel and cement constitute about 90% of the structural( l% n* r$ A% f' v; q9 w6 B; V
materials that are manufactured- y0 r/ F/ I7 C( n! d
( Westwood, Met and Mat Trans, Vol. 27 A, June 1996, 1413).. X [ S$ g4 J4 m$ c0 z3 A% O" C6 k
What, then, is steel?2 z4 h- Y% B( g0 c( I4 Z( R
A precise and concise definition of steel is not an easy thing to present because of the very. P s! @' O4 f$ {- d
large variety of alloys that bear the name. All of them, however, contain iron. We might reasonably) z& x% T, J i4 f
begin by describing a steel as an alloy which contains iron as the major component. This is only a! I; f( s: z+ i, `5 a8 V# w
beginning because there are alloys in which iron is the major constituent, that are not called steels;7 b+ y! ]6 h' F" \" u
for example, cast irons and some superalloys. The major difference between a cast iron and a steel% f, j2 S6 e. I% U7 }
is that their carbon contents lie in two different ranges. These ranges are determined by the
) `. `4 |5 h8 u, jmaximum amount of carbon that can be dissolved into solid iron. This is approximately 2% by& d. j9 w$ x; ^" _: X
weight (in FCC iron at 1146 °C). Steels are alloys that contain less than 2% carbon. Cast irons3 Z: P. Q: Q. c
contain more than 2 % carbon. Many steels contain specified minimum amounts of carbon. This( E' j! p8 q5 \
does not mean that all steels must contain substantial quantities of carbon; in some steels the1 s3 n( p7 A+ @, L* J+ a0 Z. c
carbon content is deliberately made very small and, also, the amount actually in solution is reduced
( A0 I/ ~) g; ~. ~# zfurther by the addition of alloying elements that have a strong tendency to combine with the carbon
0 T) u6 z) Q9 [to form carbides.; [% e. p7 V( j, P) x- O
Steels can be divided into two main groups; plain carbon steels and alloy steels. The latter
1 `+ K8 G" o: A1 U' gcan then be subdivided into many groups according to chemistry ( e.g. standard low alloy steels),
0 x; i& p `) Rapplications (e.g. tool steels ) or particular properties (e.g. stainless steels) etc. Let us begin with
) I1 ?7 g, s6 b# f! M22
- g! E8 g# B4 s5 E) bplain carbon steels; this group is the simplest to understand and it comprises steels that are used in# v" S$ i4 u" f
the greatest tonnage |
|