1、SAE AIR*4374 91 7743725 0000296 3 AEROSPACE INFORMATION The Engineering Sociey eA =For Advancing Mobility -Lend Sea Air and Spaces INTERNATIONAL 400 Commonwealth Drive, Warrendale, PA 15096-0001 R E Po RT AIR4394 Issued 1991-07-01 Submitted for recognition as an American National Standard I VACUUM I
2、NVESTMENT CAST PH13-8Mo CORROSION RESISTANT STEEL FOREWORD This report represents the combined effort of the membership of The Aerospace Metal s Engineering Committee of the Aerospace Materi al s Di vi si on of SAE. Specifically, the contri butions of the following are acknowledged: J. M. Shults, P.
3、E., Consulting Engineer Jay Pengra, Lockheed Corporation ,Roy Diesner, Sundstrand Aviation Operations Stan Klein, Manager, Materials and Processes, LTV Corporation Wilson Leeming, Manager of Metallurgy, Sundstrand Aviation Operations Chet May, Howmet Turbine Components Division Terry Parsons. Metall
4、 urqical Enqineer, Sundstrand Aviation Operations Dougl as Hel i copter Company as Helicopter Company Mi k Schachte: Metal 1 urical Enineer: McDonnell Leo Soffa, Manager of Mita1 lurgy, McDnne Bell Helicopter Company Carpenter Technology Corporation General Dynamics Corporation/Fort Worth D Howmet C
5、orporation Lockheed Corporation LTV Corporat i on McDonnell Dougl as Hel icopter Company Rex Precision Products Sundstrand Aviation Operations 1 Doug vision SAE Technical Board Rules provide that: “This report is published by SAE to advance the state of technical and engineering sciences. The use of
6、 this report is entirely voluntary, and its applicability and suitability for any particular use, including any patent infringement arising therefrom, is the sole responsibility of the user.” CAE reviews each technical report at least every five years at which time it may be reaffirmed, revised, or
7、cancelled. SAE invites your written commenfs and suggestions. Copyright 1991 Society of Automotive Engineers, Inc. All rights reserved. Printed in U.S.A. SAE AIR*V394 91 O 7943925 0000297 5 O SAE AIR4394 1 . 2 . TABLE OF CONTENTS SCOPE 3 REFERENCES 3 3 . PROCEDURE . 3 3.1 3.2 4 . Materials and Proce
8、ssing . 3 Testing 4 DISCUSSION 20 APPENDIX A Statistical Analysis . Mechanical Property Results 21 LIST OF TABLES Table 1 Material . 3 Table 2 Tensile Test Results . 6 Table 3 Room Temperature Fracture Toughness 7 Table 4 Fatigue Test Results. Cast Specimens. R=t0.1 . 7 Table 5 Fatigue Test Results.
9、 Machined Specimens. R=t0. 1 . 8 Table 6 Crack Growth Data. Test 1 . 9 Table 7 Crack Growth Data. Test 2 . 10 Table 8 Crack Growth Data. Test 3 . 11 Table 9 Crack Growth Data. Test 4 . 12 Table 10 Crack Growth Data. Test 5 . 13 LIST OF FIGURES Figure 1 S/N Curve for Unnotched Fatigue Behavior of PH
10、13-8 Mo (H1000) . . 5 Figure 2 Fatigue Test Results. Constant Stress Ratio. R=t0.1 14 Figure 3 Crack Growth Results. Test 1 . 15 Figure 4 Crack Growth Results. Test 2 . 16 Figure 5 Crack Growth Results. Test 3 . 17 Figure 6 Crack Growth Results. Test 4 . 18 Figure 7 Crack Growth Results. Test 5 . 19
11、 -2- SAE AIR*4394 91 E 7943725 0000298 7 E SAE AIR4394 1. 2. 3. SCOPE: An industry-wide interest has arisen with regards to the properties and capabilities of investment cast PH 13-8Mo corrosion resistant steel. Specifically of interest are the structural applications in the aerospace industry for t
12、his product heat treated to the H1000 condition. The objective of this AMEC cooperative test program was to generate and compile useful data for aerospace structural evaluation of investment cast PH 13-8Mo heat treated to H1000. The focus of the test program was the determination of overall mechanic
13、al properties, fatigue, fracture toughness, and crack growth data along with basic microstructural evaluation of the investment cast materi al. Additional objectives included the evaluation of mechanical property variations between cast and machined tensile specimens and evaluation of microstructura
14、l constituents. Al 1 testing was performed to determine the suitability of PH 13-8Mo, H1000 investment castings for use in the aerospace industry. REFERENCES : AMS 5629 Bars, Forgings, Rings, and Extrusions, 13Cr-8.ONi-2.2Mo-l.lAl , Vacuum Induction P1 us Vacuum Consumable Electrode Melted, Sol utio
15、n Heat Treated, Precipitation Hardenable PROCEDURE : 3.1 Materials and Processing: The material tested was vacuum induction melted in two heats, having the following compositions conforming to AMS 5629 (see Table 1): TABLE 1 Heat C Mn Si P S Cr Ni Mo Al. 1 0.018 0.0065 0.0052 0.0017 0.0016 12.70 7.9
16、7 2.11 1.11 2 0,024 0.0060 0.0063 0.0016 0,0016 12.59 7.98 2.13 1.15 The material was investment cast with a selective insulated wrap, poured under vacuum. 2725OF f 50. Air cooling followed vacuum casting. Mold temperature was 2150OF f 50 and metal temperature was -3- SAE AIRg4394 91 7943725 0000299
17、 9 SAE AIR4394 3.1 3.2 (Conti nued) : Thermal treatment processing of the material consisted of the following: a. Homogenize at 21OOOF f 25 for 90 min in vacuum with argon gas fan cool to room temperature. b. Solution treat at 17OOOF f 15 for 60 min in vacuum with argon gas fan cool followed by a wa
18、ter cool to below 60OF. c. Age at 1000F for 4 h in air with rapid air cool. Test i ng : Room temperature mechani cal property tests were conducted on machined specimens and specimens which were cast to size for the purpose of establishing strength guidelines and for making a comparison between the t
19、wo conditions. strength properties of the cast-to-size and machined-to-size specimens were not statistically equivalent by a T-test comparison. However, since the values are slightly lower in both cases for the cast-to-size specimens, combining the data seems reasonable. were statistically equivalen
20、t using an identical statistical analysis. However, due to the rather large standard deviations, the statistical minimums are very low. All statistical analyses of the mechanical property data are presented in Appendix A. The results are presented in Table 2. The ultimate and yield The ductility of
21、the two specimen types Plane strain fracture toughness was evaluated on five specimens primarily for information purposes. consistent for each test group. The results presented in Table 3 were relatively A series of axial load fatigue tests were conducted. so that cycles to failure ranged between lo
22、3 and 10. as-cast specimens from heat 2 at constant stress-ratio, R=t0.1, was conducted on 22 specimens to develop a satisfactory S/N curve. with an S/N curve derived from 14 machined-to-size specimens. stress-ratio results are presented in Tables 3 and 4 and plots of the data are combined in Figure
23、 2. machined-to-size specimens is also shown in Figure 1, for comparison with fatigue data on rolled bar as reported by ARMCO. Stresses were selected A single test using A comparison was made The constant The fatigue curve developed from tests of The final results presented are comprised of data fro
24、m a series of compact tension tests performed on specimens machined from plate stock to develop representative crack growth data for PH 13-8Mo, H1000. Five individual tests were conducted. respective plots in Figures 3 through 7. Results are presented in Tables 5 through 9 with their -4- SAE AIR4394
25、 o l- O b 7 O o 7 O o T O t T- O 0 l- O Li O I4 rl Y m ., U F O T- SAE AIR*4394 91 7943725 00003L3 T SAE AIR4394 + + + + + + + + + f + + + J + + + + + 1 + + + + + + + + 3 O Y= III I I I I 1Ii.i I I I I t tiill I I I I Ili11 I I I I t O l- f O r P O r cy O Y- c I .- F O Y- b (B 1 Y ai cn t E h U .- a
26、 t 0 r S (B a a, L u cr) I- n v) c c 3 v) Q) e Y u rd L o I LD W cd c5 U LL O O SAE AIRt4394 91 m 7943725 O000314 1 m SAE AIR4394 + + + + + + + + + + + + + + + + + $ + + + + 7 O T= W I r O .Q O l- b I T O N r O x $-r cn (B a, L ti SAE AIR*4394 91 W 7943725 00003i15 3 W SAE AIR4394 4. DISCUSSION: The
27、 statistical analysis of mechanical property results from the two specimen conditions, as-cast and machined to size, indicated that the ductility is essentially equal for the two conditions. However, the data possessed a large degree of scatter as reflected by the rather large standard deviations in
28、 both the elongation and reduction of area. The ultimate and yield strength results indicated only slightly lower values for the cast to size specimens. the difference was only slight, the data was combined for the purpose of determining the statistical and suggested guide1 ines for mechanical prope
29、rties. rounding up or down to the nearest 5 ksi. were determined by using values of approximately 75% of the actual values due to the effect of the scatter on the ductility results. Since The suggested strength guidelines listed in Table 11 reflect a In addition, the ductility minimums TABLE 11 Stat
30、istical Statistical Suggested Suggested Min Max Min Max Ultimate Strength, ksi 196.9 210.9 195 215 Yield Strength, ksi 183.9 206.3 180 210 El ongat i on (Percent) 1 .o - 3 13 - - - Reduct i on of Area (Percent) 1.5 Microstructural evaluation of a sample of PH 13-8Mo, H1000 with internal hardness of
31、43 R, revealed a largely martensitic structure with sparsely scattered spheroidal ferrite precipitates. The structure appeared typical for solution treated and aged 13-8Mo material. No effort was made in this program to correlate the effect of various microstructural constituents on the properties o
32、f the material. PREPARED BY SAE AMS COMMITTEE B - 20 - SAE AIR*4394 91 m 7943725 00003Lb 5 m SAE AIR4394 5 r W .-I a 2w Y I- LL 3 t NNNNNN-I-I-INNNNNNNNNNNNNNNNNNNNN 000000000000000000000000000000 000000000000000000000000000000 wwwwwwwwwwwwwwwwwwwwwwwwwwwwww IsIIIIIIIITIIIIIIrIIIIxsIIIxII ccccI-I-I-
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