1、 This document is restricted and may not be sent outside Navistar, Inc. or reproduced without permission from IPD Technical Standards Team. Suppliers are required to assume all patent liability. 2018 by Navistar, Inc. OCTOBER 2001 Page 1 of 21 NAVISTAR, INC. Material, Parts, and Process Specificatio
2、ns (MPAPS) NUMBER: MPAPS AT-3 Former Designation: CEMS AT-3 TITLE: Method Of Calculating DIB And DIC For Heat Treatable Steels CURRENT REV No.: 1802 DATE: Feb. 2018 WRITTEN/EDITED BY: W. Cook APPROVED BY: R. Goluch SUPERSEDES: Rev. October 2001 PRINTED COPIES OF THIS DOCUMENT MUST BE VERIFIED FOR CU
3、RRENT REVISION This specification may involve hazardous materials, equipment, and procedures. This specification does not purport to address all of the safety issues associated with its use. The user is responsible to consult appropriate safety and health practices and to determine the applicability
4、 of regulatory limits prior to use. 1.0 SCOPE This method covers a procedure for calculating minimum, mean, and maximum ideal critical diameters (DI) for base chemical composition (DIB) and for the case chemical composition DIC of wrought and cast heat treatable steels. The calculated values of D ar
5、e intended to serve as a guide to the range of hardenability that can be expected for a grade or family of steels. Steels without standard hardenability (H) bands can therefore be compared to those with H bands. The calculated DIs are not intended to mean that a DI value for a particular heat of ste
6、el will never exceed the stated minimum or maximum, but that most of the time the DI will fall within the stated DI range. Calculated DIs are normally used only for comparative purposes but they may also be used for calculating hardenability bands. 2.0 PROCEDURE The DIB is defined as the diameter of
7、 a steel bar that will have a 50 percent martensitic structure at the center when quenched in an ideal quench. The DIC is a calculated measure of hardenability. It is defined in terms of a distance rather than a diameter. This distance is that location from the quenched end of a 1% carbon carburized
8、 Jominy Bar to 10% non-martensitic transformation product. 2.1 Both the DIB and D IC can be calculated from the chemical analysis and grain size of the steel. The procedure consists of multiplying the carbon hardenability factor by a factor for the percent of each alloying element. For DIC calculati
9、ons a 1.00% carbon factor is used. Table II and III in this specification list the logarithms of the various multiplying factors so that only additions are needed to obtain the sum of the hardenability characteristics. Table IV is then used to convert this sum to either DIB or DIC values. 2.2 When c
10、alculating the minimum, mean and maximum DIB and minimum DIC for any grade of steel, with a given chemistry range, the calculation procedure shown in Table I applies (procedure applies to the standard chemical composition range, not the H steel composition, see example page 2). This procedure does n
11、ot apply to the carbon-manganese-boron steels. The carbon-boron steels use the full standard chemical composition range instead of the + 25% range. 2.3 Example 94B17 H 2.3.1 H Steel chemical composition: 0.14-0.20% carbon; 0.70-1.055 manganese; 0.15-0.35% silicon; 0.25-0.65% nickel; 0.25 - 0.55% chr
12、omium; 0.08-0.15% molybdenum; 0.0005% minimum boron. NUMBER: MPAPS AT-3 TITLE: Method of Calculating DIB AND DIC For Heat Treatable Steels CURRENT ISSUE DATE: 1802 This document is restricted and may not be sent outside Navistar, Inc. or reproduced without permission from IPD Technical Standards Tea
13、m. Suppliers are required to assume all patent liability. 2018 by Navistar, Inc. FEBRUARY 2018 Page 2 of 21 2.3.2 Standard steel chemical composition: 0.15-0.20% carbon; 0.75-1.00% manganese; 0.15-0.35% silicon; 0.30-0.60% nickel; 0.30-0.50% chromium; 0.08-0.15% molybdenum; 0.0005% min boron. Table
14、I Procedure for DI Calculation Element DIB (Base) DIC (Case) Minimum Mean Maximum Minimum % of Element Used For DI Calculation Factors* Carbon Minimum of Specified Range Mean of Specified Range Maximum of Specified Range 1.00 Alloying Element (Except Boron) Minimum Specified + 25% of Range Minimum S
15、pecified +50% of Range Maximum Specified -25% of Range Minimum Specified + 25% of Range Boron (Based On Carbon Level) Factor For Minimum of Specified Carbon Range Factor for Mean of Specified Carbon Range Factor for Maximum of Specified Carbon Range Not Applicable Residuals* : Nickel Chromium Molybd
16、enum 0.01 0.02 0.01 0.03 0.05 0.02 0.05 0.08 0.03 0.01 0.02 0.01 * Residual alloy contents are used where nickel, chromium, and/or molybdenum contents are not known or not specified. Values listed are typical for a low residual mill. * Composition for DIB and DIC calculations will be in increments o
17、f 0.01%. The rounding procedure will as be shown in the following example: Example: Manganese 0.75 1.05% Minimum 0.75 + 0.075 = 0.825 use 0.82% Mean 0.75 + 0.15 = 0.90 use 0.90% Maximum 1.05 0.075 = 0.975 use 0.98% 2.3.3 Minimum DIB use: 0.15% carbon; 0.81% manganese; 0.20% silicon; 0.37% nickel; 0.
18、355 chromium; 0.11% molybdenum; boron factor for 0.15% carbon. 2.3.4 Mean DIB use 0.17% carbon; 0.87% manganese; 0.25% silicon; 0.45% nickel; 0.40% chromium; 0.11% molybdenum; boron factor for 0.17% carbon. 2.3.5 Maximum DIB use: 0.20% carbon; 0.94% manganese; 0.30% silicon; 0.45% nickel; 0.40 chrom
19、ium; 0.11% molybdenum; boron factor for 0.20% carbon. 2.3.6 Minimum DIC use: 1.00% carbon; 0.81% manganese; 0.20% silicon; 0.37% nickel; 0.35% chromium; 0.10% molybdenum. 2.4 Sample Calculation; 94B17H, Minimum DIB and DIC . Analysis DIB Factors DIC Factors Base Carbon 0.15% 0.5185 Case Carbon 1.00%
20、 0.9191 Manganese 0.81% 0.3620 0.2350 Silicon 0.20% 0.000 0.0569 Nickel 0.37% 0.0457 0.0500 Chromium 0.35% 0.0899 0.1492 Molybdenum 0.10% 0.0453 0.1038 Boron 0.0005% 0.3096 Sum 1.3710 1.514 NUMBER: MPAPS AT-3 TITLE: Method of Calculating DIB AND DIC For Heat Treatable Steels CURRENT ISSUE DATE: 1802
21、 This document is restricted and may not be sent outside Navistar, Inc. or reproduced without permission from IPD Technical Standards Team. Suppliers are required to assume all patent liability. 2018 by Navistar, Inc. FEBRUARY 2018 Page 3 of 21 DI Inches 2.35 3.25 Millimeters 59.7 82.6 3.0 STANDARD
22、CALCULATION TABLES FOR DETERMINATION OF THE CRITICAL DIAMETERS The base and case hardenability factors listed in Tables II and III, respectively, will be considered as the Companys standard means for calculating the ideal critical diameters DIB and DIC , respectively, which may be used as a basis fo
23、r hardenability calculations when comparing different grades of steel. 3.1 The carbon factor for DIB calculations are shown in Table II. For purposes of standardization in comparing different grades of steel, the carbon factors shown for Grain Size No. 7 are used in DIB calculations. 3.2 The alloy D
24、IB factors listed herein are for manganese, silicon, nickel, copper (assumed the same as nickel), chromium, molybdenum and boron. There are single alloy and multialloy DIB factors for molybdenum, because of alloy interactions. Multialloy molybdenum factors are used instead of single alloy factors fo
25、r steels with a 0.75% minimum nickel and 0.25% minimum molybdenum in combination. Boron hardenability factors are a function of carbon content. 3.3 The carbon factors for DIC calculations are the carbon factors shown in Table III. For purposes of standardization in comparing different grades of stee
26、l, the factor for 1.00% carbon is used for DIC calculations. 3.4 The alloy DIC factors listed herein are for manganese, silicon, nickel, copper (assumed the same as nickel), chromium and molybdenum. There are single alloy and multialloy factors for silicon. Multialloy silicon DIC factors are used fo
27、r steels with 1.00% minimum or greater nickel and 0.15% minimum molybdenum in combination. DIC calculations are based on direct quenching. If reheating and quenching are employed, additional alloy interactions occur and the factors listed in Table III are not applicable. 3.5 Calculated values of DIB
28、 and DIC for some standard North American and Overseas steels are listed in Tables V and VI. These calculated values are based on the corresponding standard chemical composition ranges for each grade listed. 3.6 Correlations of these calculated DIB and DIC values with actual hardenability data devel
29、oped for “H” band steels is well established for North American grades. The factors listed in Tables II and III have been based on this relationship. The correlation for Overseas steels however may not be as accurate. In developing “H” band steels overseas, the techniques of expanding on standard st
30、eel chemistry ranges differs from the methods of North America. The procedures used for North American Grades are consistent and uniform, while overseas adjustments tend to be nonuniform with variations from grade to grade. Overseas methods also vary with each country. Calculated DIB and DIC values
31、listed in Table VI for Overseas steels are therefore considered as estimates with maximum confidence on the mean DIBs. Reference: “Design Data for the CHAT Analysis of Steels,” ER Report No. 89, June 1972; and “Modifications to ER Report No. 89,” June, 1973. NUMBER: MPAPS AT-3 TITLE: Method of Calcu
32、lating DIB AND DIC For Heat Treatable Steels CURRENT ISSUE DATE: 1802 This document is restricted and may not be sent outside Navistar, Inc. or reproduced without permission from IPD Technical Standards Team. Suppliers are required to assume all patent liability. 2018 by Navistar, Inc. FEBRUARY 2018
33、 Page 4 of 21 TABLE II LOGARITHMS OF HARDENABILITY FACTORS FOR CALCULATION OF BASE IDEAL CRITICAL DIAMETERS, DIB, from CHEMICAL COMPOSITION Carbon Factors ASTM Grain Size Number % Carbon 4 . 5 . 6 . 7 . 8* 9 . 10 . 0.10* 0.4265 0.11* 0.4472 0.12* 0.4669 0.13* 0.4814 0.14* 0.4997 0.15* 0.5911 0.5563
34、0.5237 0.5185 0.4698 0.4362 0.4014 0.16* 0.6082 0.5737 0.5425 0.5289 0.4883 0.4547 0.4218 0.17* 0.6253 0.5911 0.5613 0.5391 0.5068 0.4732 0.4422 0.18* 0.6424 0.6085 0.5801 0.5465 0.5253 0.4917 0.4626 0.19* 0.6595 0.6259 0.5989 0.5575 0.5438 0.5102 0.4830 0.20 0.6767 0.6435 0.6180 0.5682 0.5623 0.528
35、9 0.5038 0.21 0.6902 0.6576 0.6319 0.5911 0.5755 0.5435 0.5171 0.22 0.7037 0.6717 0.6458 0.6129 0.5887 0.5581 0.5304 0.23 0.7172 0.6858 0.6597 0.6335 0.6019 0.5727 0.5437 0.24 0.7307 0.6999 0.6736 0.6484 0.6151 0.5873 0.5570 0.25 0.7443 0.7143 0.6875 0.6682 0.6284 0.6021 0.5705 0.26 0.7553 0.7253 0.
36、6991 0.6767 0.6402 0.6142 0.5826 0.27 0.7663 0.7363 0.7107 0.6902 0.6520 0.6263 0.5947 0.28 0.7773 0.7473 0.7223 0.7033 0.6638 0.6384 0.6068 0.29 0.7883 0.7583 0.7339 0.7160 0.6756 0.6505 0.6189 0.30 0.7993 0.7694 0.7459 0.7283 0.6875 0.6628 0.6314 0.31 0.8087 0.7791 0.7552 0.7380 0.6964 0.6726 0.64
37、11 0.32 0.8181 0.7888 0.7645 0.7482 0.7053 0.6824 0.6508 0.33 0.8275 0.7985 0.7738 0.7574 0.7142 0.6922 0.6605 0.34 0.8369 0.8082 0.7831 0.7672 0.7231 0.7020 0.6702 0.35 0.8463 0.8182 0.7924 0.7745 0.7324 0.7118 0.6803 0.36 0.8532 0.8254 0.7994 0.7818 0.7398 0.7190 0.6874 0.37 0.8601 0.8326 0.8064 0
38、.7868 0.7472 0.7262 0.6945 0.38 0.8670 0.8398 0.8134 0.7924 0.7546 0.7334 0.7016 0.39 0.8739 0.8470 0.8204 0.7973 0.7620 0.7406 0.7087 0.40 0.8808 0.8543 0.8274 0.8028 0.7694 0.7482 0.7160 0.41 0.8863 0.8597 0.8330 0.8096 0.7753 0.7534 0.7211 0.42 0.8918 0.8651 0.8386 0.8162 0.7812 0.7586 0.7262 0.4
39、3 0.8973 0.8705 0.8442 0.8195 0.7871 0.7638 0.7313 0.44 0.9028 0.8759 0.8498 0.8228 0.7930 0.7690 0.7364 0.45 0.9085 0.8814 0.8555 0.8274 0.7993 0.7745 0.7419 0.46 0.9126 0.8858 0.8594 0.8325 0.8033 0.7787 0.7454 0.47 0.9167 0.8898 0.8633 0.8357 0.8073 0.7829 0.7489 0.48 0.9208 0.8940 0.8672 0.8387
40、0.8113 0.7871 0.7524 0.49 0.9249 0.8982 0.8711 0.8421 0.8153 0.7913 0.7559 0.50 0.9294 0.9025 0.8751 0.8453 0.8195 0.7959 0.7597 * Extrapolated * ASTM Grain Size No. 7 is the standard used for comparative purposes NUMBER: MPAPS AT-3 TITLE: Method of Calculating DIB AND DIC For Heat Treatable Steels
41、CURRENT ISSUE DATE: 1802 This document is restricted and may not be sent outside Navistar, Inc. or reproduced without permission from IPD Technical Standards Team. Suppliers are required to assume all patent liability. 2018 by Navistar, Inc. FEBRUARY 2018 Page 5 of 21 TABLE II (continued) Carbon Fac
42、tors % Carbon ASTM Grain Size No. 7* . % Carbon ASTM Grain Size No. 7* . % Carbon ASTM Grain Size No. 7* . % Carbon ASTM Grain Size No. 7* . 0.51 0.8492 0.61 0.8780 0.71* 0.8987 0.81* 0.9053 0.52 0.8513 0.62 0.8808 0.72* 0.8998 0.82* 0.9058 0.53 0.8543 0.63 0.8837 0.73* 0.9009 0.83* 0.9058 0.54 0.85
43、73 0.64 0.8865 0.74* 0.9020 0.84* 0.9063 0.55 0.8615 0.65 0.8876 0.75* 0.9031 0.85* 0.9063 0.56 0.8663 0.66 0.8893 0.76* 0.9036 0.86* 0.9069 0.57 0.8675 0.67 0.8921 0.77* 0.9042 0.87* 0.9069 0.58 0.8692 0.68 0.8949 0.78* 0.9042 0.88* 0.9080 0.59 0.8722 0.69 0.8960 0.79* 0.9047 0.89* 0.9080 0.60 0.87
44、51 0.70 0.8976 0.80* 0.9047 0.90* 0.9085 Boron Factors* % Carbon Boron Factor . % Carbon Boron Factor . % Carbon Boron Factor . % Carbon Boron Factor . 0.10 0.3284 0.26 0.2648 0.42 0.1931 0.58 0.1072 0.11 0.3243 0.27 0.2625 0.43 0.1903 0.59 0.1004 0.12 0.3201 0.28 0.2577 0.44 0.1847 0.60 0.0969 0.13
45、 0.3160 0.29 0.2529 0.45 0.1790 0.61 0.0899 0.14 0.3118 0.30 0.2480 0.46 0.1732 0.62 0.0828 0.15 0.3096 0.31 0.2455 0.47 0.1673 0.63 0.0755 0.16 0.3054 0.32 0.2405 0.48 0.1644 0.64 0.0719 0.17 0.3010 0.33 0.2355 0.49 0.1584 .065 0.0645 0.18 0.2989 0.34 0.2304 0.50 0.1523 0.66 0.0569 0.19 0.2945 0.35
46、 0.2279 0.51 0.1461 0.67 0.0492 0.20 0.2900 0.36 0.2201 0.52 0.1430 0.68 0.0454 0.21 0.2856 0.37 0.2175 0.53 0.1367 0.69 0.0334 0.22 0.2833 0.38 0.2122 0.54 0.1303 0.70 0.0294 0.23 02788 0.39 0.2095 0.55 0.1239 0.71 0.0212 0.24 0.2742 0.40 0.2041 0.56 0.1206 0.72 0.0128 0.25 0.2695 0.41 0.1987 0.57
47、0.1139 0.73 0.0086 * Extrapolated * ASTM Grain Size No. 7 is the standard used for comparative purposes. * Boron multiplying factor = 1 + 1.76 (0.75 - % carbon). The logarithm of the calculated factor has been used. NUMBER: MPAPS AT-3 TITLE: Method of Calculating DIB AND DIC For Heat Treatable Steel
48、s CURRENT ISSUE DATE: 1802 This document is restricted and may not be sent outside Navistar, Inc. or reproduced without permission from IPD Technical Standards Team. Suppliers are required to assume all patent liability. 2018 by Navistar, Inc. FEBRUARY 2018 Page 6 of 21 TABLE II (continued) Alloy Factors Molybdenum* . % of Alloys Manganese Silicon Nickel Chro
