1、 ENGINEERING STANDARDS Test Procedure SUPERCEDED EDS-T-7104 Method of Macrostructure Test for Steel This standard may be applied only for current projects. It is Superceded for all future projects and replaced by ISO4969. I8 *A ) 9: 4G - Note: 8 E:48t G8 =97 FF7 957%L+ , FG P-P Program .Bd# ISO4969
2、) $4=F7 957F$ . Copyright 2011 General Motors Company All Rights Reserved July 2011 Originating Department: GM Korea Engineering Standards Page 1 of 10 Version : 4 1 Scope Note: Nothing in this standard supersedes applicable laws and regulations. Note: In the event of conflict between the Korean and
3、 English language, the Korean language shall take precedence. 1.1 Purpose. This standard aim at establishing the testing method of inspecting internal defects of forged or rolled steels by etching method and the evaluation standards for these defects. 1.2 Applicability. This standard specifies the t
4、esting method of detecting the macrostructure of forged or rolled steels by etching a section of steels with hydrochloric acid, ammonium copper chloride or aqua regia. 2 References Note: Only the latest approved standards are applicable unless otherwise specified. 2.1 External Standards/Specificatio
5、ns. JIS G 0553 KS D 0210 2.2 GM Standards/Specifications. None 2.3 Additional References. None 3 Resources 3.1 Test Piece. Flat test piece shall be cut at a right angle to the working direction of forged or rolled steel. Surface of the test piece to be examined shall usually be finished with dry or
6、wet grinder and shall be degreased prior to testing. 1 P7 :0 : ., E:48 68p) FF F7 2P) $3: 6 .4627 94 3)1 “W#$ . 4.2.1.1.4 I88 9*7 &d* E:4 .4488t E 17 &d*$ . 4.2.1.2 70G%6+#- (/x95 A $+8 I87 87 ). 4.2.1.2.1 ,p 1000 ml7 )67 70G%6+# 100 350 g8 /x8) 7FF 8x .468p) 17F$ . 4.2.1.2.2 .48t 1772P 44F$ . 4.2.1
7、2.3 I88 9*7 &d* E:4 .4488t E 17 &d*$ . 4.2.1.2.4 dA .468 1B -C I88 1B# 701-7 :4F$ . 4.2.1.2.5 .48 :FF# % 6| % 8 I88 E+7 2QF#$ , 8 2Q,p8t .48 ! G 4D8x 5 .8 )d :E7 -?F$4 /) 3 ! G8p) 9PF , 95$-F 1B4 %T &: 88x -L.)F$ . (.(B 3 10G ). GM KOREA ENGINEERING STANDARDS EDS-T-7104 Copyright 2011 General Motor
8、s Company All Rights Reserved July 2011 Page 3 of 10 Version : 4 Table 1: Standard Etching Time Periods for Carbon Steel and Alloy Steel / E 1: A2I , F.H 2l9IF , -H(8p) =2 9F G , 8U6|8p) DD9IF$ . 9:G DD9I 47# 4.2.3.2 F8x 2(F$ 9$ . 5 4G $8Bd .$=l9 . 6 6|987 $4F 7 9 ., E:48t 88G ,p: , 86 , 8/x &%8x E
9、FF 3L 8$ . ., E:48t 87 $4F 170 4)%P +& 6|98 ,l9P8 F8x 9P4F:# 6#$ . &d(2P 17 987 95FF 6|980 I 1B* 9DF , -18 9PF 728 957 7 .* 9IF# 8t ., E:4 1788 =y8 1F8$ . 7 768 9I8 7.1 98,l 76 (.$ =l9 ). 3L:1 9I : I8 8 F & 3L:18p) -P$ F 8= 9I8 $9 D# 67$ G7$ , GIB* ,$4) 4: 8# . GM KOREA ENGINEERING STANDARDS EDS-T-7
10、104 Copyright 2011 General Motors Company All Rights Reserved July 2011 Page 5 of 10 Version : 4 Ingot Pattern: A pattern displaying variation in the degree of etching effect caused by change in crystalline state or by segregation of components during solidification of steel. Centre Segregation: Var
11、iation in the degree of etching effect in the central portion caused by segregation during solidification of steel. Looseness: A spongy pattern on the entire section. Pit: A spotty pattern of small visible cavities caused by etching on the entire section. Blowhole: Blowholes or pinholes left on the
12、central portion of steel without being completely smashed up. Non-metallic Inclusion: Non-metallic substances visible to the naked eye. Pipe: A primary or secondary pipe caused by shrinkage during solidification of steel left in its centre without being completely smashed up. Hair Crack: Fine hair c
13、racks on steel sections that are appreciable by etching. Center Defect: Cracks caused in the centre of steel due to improper forging or rolling. Surface Flaw (Seams, Laps, etc): Flaws caused by sub-surface blowholes, rolling or forging or other flaws produced on the outside surface of steel. 7.2 Acr
14、onyms, Abbreviations, and Symbols. Not applicable. 8 Coding System This standard shall be referenced in other documents, drawings, etc., as follows: Test to EDS-T-7104 8.1 Classification. 8.1.1 Macrostructure over the entire section: Dendrite, ingot pattern, looseness, pit, etc. 8.1.2 Macrostructure
15、 in centre portion: Segregation, looseness, pit, etc. 8.1.3 Blowholes, non-metallic inclusion, pipe, and other defects, etc. 8.2 Letter Symbol. 8C DBh : I8 8 4 9I 1B8 -G D# 2e.8 D=7 8F2P I8 $+7 8C GIB8 .48 “$=4 !A! . :E4 . D2Q : I8 8 4 2e.8 D=7 8F I8 :E4 .7 .48 “$=4 !A! . $): : I8 $+7 !A! F+18 9: .
16、FpC : .4G7 I8 $+7 8U6|8p) .0 3L 8# A d) 9D18 +8 2h . dE : /H)7 Gl7 D# Ft Gl7 (Pin hole)8 7x98H 6=%L: 6 I8 :E4 .7 H958x !h . P8,p : 8U6|8p) 4=d%L# /x4 : I8 8 3L4 -P2F 8= D# 8= D8F84 7x98H 6=%L: 6 , I8 :E4 .7 , H958x !h . +2l 7( : .4 G7 I8 $+7 -,2lF +-P18p) !A! H . :E4 . D7( : .95$-F $9 D# 67$)9I8p) 8
17、F7 :E4 . D7(8 2h . :0- H : :0- dE 7 8F H -C 67$ -C $97 8F H , dA I88 7:0.7 2h H . 7.2 66 -C dGl . F$-1F 68 . 8 Ed - $* ,l2P! $+ &%72P ., E:48 87%T &# $80 M8 EdF$ . Test to EDS-T-7104 8.1 .* . 8.1.1 $+ 98=7 !A! 9: : 3L:1 9I , 8C DBh , $): , FpC &% . 8.1.2 :E4 .8 9: : D2Q , $): , FpC &% . 8.1.3 dE , P
18、8,p , D8F8&% dA F . 8.2 E4 dGl . Dendrite / 3L:19I Ingot pattern / 8CDBh Looseness / $): Pit / FpC Centre segregation / :E4 .D2Q Centre looseness / :E4 .$): D I L T Sc Lc Centre pit / :E4 .FpC Shrunk pipe / 3L4 Hair crack / +2l7( Centre crack / :E4 .D7( Surface flaw / :0-H Non-metallic inclusion / P
19、8,p Blowhole / dE Tc P H F K N B GM KOREA ENGINEERING STANDARDS EDS-T-7104 Copyright 2011 General Motors Company All Rights Reserved July 2011 Page 6 of 10 Version : 4 8.3 Indication System. The letter symbol for classification shall be used in order prescribed in 8.1, as given below. Example: DT -
20、Sc - N (The appearance of dendritic crystal and pit on the whole section and existence of centre segregation and non-metallic inclusion). 9 Release and Revisions This standard was originated in November 1990. It was first approved by Engineering Standard Committee in November 1990. It was first publ
21、ished in November 1990. 8.3 E4 - . 6x( .(d7t M8 8.1 F .*8 3P2P7 &d( 5 dGl) EdF$ . .(d : DT - Sc - N ($+ 98=7 3L:1 9I -C FpC , :E4 .7 D2Q , ,* P8,p8 4=d% .) 9 9P9I -C P9I 8)Y ., E:48t 1990“x 1187 E:4 -Gl4 .7 %L6 , d3TE:41,h7 8F 1990 “x 11 87 38%L6$ . ., E:48t 1990 “x 11 87 ) 9P9I / -PF%L6$ . Issue /
22、P9I8)Y Publication Date / 38 88 Description (Organization) / 9PP9I76 (:04.2P ) 4 JUL 2011 Apply new Engineering Standard Template. Superceded (Corrosion / Metallurgical Material Lab Team) / 4 d3TE:4 64 957 . F9I957 =* (28*4G D4 ) GM KOREA ENGINEERING STANDARDS EDS-T-7104 Copyright 2011 General Motor
23、s Company All Rights Reserved July 2011 Page 7 of 10 Version : 4 Attached Figure: Classification of Killed Steel Macro-Structure / .$ : A& I *8A ) 9: .* Classification / .* Class / 9- (1) (2) GM KOREA ENGINEERING STANDARDS EDS-T-7104 Copyright 2011 General Motors Company All Rights Reserved July 201
24、1 Page 8 of 10 Version : 4 Classification / .* Class / 9- (1) (2) GM KOREA ENGINEERING STANDARDS EDS-T-7104 Copyright 2011 General Motors Company All Rights Reserved July 2011 Page 9 of 10 Version : 4 Classification / .* Class / 9- (3) GM KOREA ENGINEERING STANDARDS EDS-T-7104 Copyright 2011 General Motors Company All Rights Reserved July 2011 Page 10 of 10 Version : 4 Classification / .* Class / 9- (3)
