1、AGMA INFORMATION SHEET(This Information Sheet is NOT an AGMA Standard)AGMA923-B05AGMA 923-B05AMERICAN GEAR MANUFACTURERS ASSOCIATIONMetallurgical Specifications for SteelGearingiiMetallurgical Specifications for Steel GearingAGMA 923-B05CAUTION NOTICE: AGMA technical publications are subject to cons
2、tant improvement,revision, or withdrawal as dictated by experience. Any person who refers to any AGMAtechnical publication should be sure that the publication is the latest available from the As-sociation on the subject matter.Tables or other self-supporting sections may be quoted or extracted. Cita
3、tions shouldread: See AGMA 923-B05, Metallurgical Specifications for Steel Gearing, published bythe American Gear Manufacturers Association, 500 Montgomery Street, Suite 350,Alexandria, Virginia 22314, http:/www.agma.org.Approved May 3, 2005ABSTRACTThis document identifies metallurgical quality char
4、acteristics which are important to the performance of steelgearing. The AGMA gear rating standards identify performance levels of gearing by heat treatment method andgrade number. For each heat treatment method and AGMA grade number, acceptance criteria are given forvarious metallurgical characteris
5、tics identified in this document.Published byAmerican Gear Manufacturers Association500 Montgomery Street, Suite 350, Alexandria, Virginia 22314Copyright 2005 by American Gear Manufacturers AssociationAll rights reserved.No part of this publication may be reproduced in any form, in an electronicretr
6、ieval system or otherwise, without prior written permission of the publisher.Printed in the United States of AmericaISBN: 1-55589-848-3American GearManufacturersAssociationAGMA 923-B05AMERICAN GEAR MANUFACTURERS ASSOCIATIONiii AGMA 2005 - All rights reservedContentsPageForeword iv.1 Scope 1.2 Normat
7、ive references 1.3 Definitions 3.4 Procedures 11.5 Metallurgical requirements 14Bibliography 31.Tables1 Metallurgical characteristics for through hardened gearing 15.2 Metallurgical characteristics for carburize and hardened gearing 17.3 Metallurgical characteristics for induction or flame hardened
8、gearing 224 Metallurgical characteristics for nitrided gearing 27Figures1 Continuous carbide network 42 Semi-continuous carbide network 4.3 Discontinuous carbides 44 Dispersed carbides 4.5 Solid on shaft pinion blank 5.6 Bore style gearing blank 5.7 Disc style gearing blank 5.8 Web style gear blank
9、69 Intergranular oxidation in carburized gearing 710 Non-martensitic transformation products in carburized gearing 8.11 Tempered martensite and 5% retained austenite in carburized gearing 1012 Tempered martensite and 20% retained austenite in carburized gearing 10.13 Tempered martensite and 30% reta
10、ined austenite in carburized gearing 10.14 Variations in hardening pattern obtainable on gear teeth with flame orinduction hardening 26AGMA 923-B05 AMERICAN GEAR MANUFACTURERS ASSOCIATIONiv AGMA 2005 - All rights reservedForewordThe foreword, footnotes and annexes, if any, in this document are provi
11、ded forinformational purposes only and are not to be construed as a part of AGMA InformationSheet 923-B05, Metallurgical Specifications for Steel Gearing.In November, 1984, an ad hoc Metallurgy and Gear Rating Committee met to define thefactors required to qualify the various metallurgical quality g
12、rades that were to be introducedinto the gear rating standard that eventually became ANSI/AGMA 2001- B88, FundamentalRating Factors and Calculation Methods for Involute Spur and Helical Gear Teeth.In May, 1988, ANSI/AGMA 6033-A88, Standard for Marine Propulsion Gear Units - Part 1,Materials, was pub
13、lished using a short list of metallurgical factors in table form.In September, 1988, ANSI/AGMA 2001-B88 was published using metallurgical factors intable form.Starting in July, 1992, AGMA representatives participated in writing ISO 6336-5,Calculation of Load Capacity of Spur and Helical Gears - Part
14、 5: Strength and Quality ofMaterials, which was a modification of the tables in ANSI/AGMA and DIN Standards.In February, 1993, AGMA 6002-B93, Design Guide for Vehicle Spur and Helical Gears,waspublished using a modified version of the tables used in ANSI/AGMA 2001-B88.In September, 1993, the AGMA Me
15、tallurgy and Materials Committee accepted the task ofconsolidating the various tables to avoid redundancies and conflicting requirements, andstarted work on AGMA 923-A00, Metallurgical Specifications for Steel Gearing.In January, 1995, a revised ANSI/AGMA 2001-C95 was published using a version of th
16、eANSI/AGMA 2001-B88 tables as revised by the AGMA Helical Gear Rating Committee.In November, 1997, a revised ANSI/AGMA 2003-B97, Rating the Pitting Resistance andBending Strength of Generated Straight Bevel, Zerol Bevel and Spiral Bevel Gear Teeth,was published using a version of the ANSI/AGMA 2001-
17、B88 tables as revised by the AGMABevel Gearing Committee.The committee reviewed all metallurgical tables of the gear rating standards ANSI/AGMA2001-B88, ANSI/AGMA 2003-A86, and ISO 6336-5:1996 and their proposed revisions todevelop consolidated tables describing the metallurgical characteristics ass
18、ociated witheach specific type of heat treatment and metallurgical quality grade. Effort was made toreference ISO specifications where possible. The consolidated tables were submitted tothe gear rating committees for their agreement and are published here for reference byother standards.AGMAs goal i
19、s to develop a consistent metallurgical specification which reflects the qualityrequirements for steel gearing. AGMA 923-A00 was such a document, and was intended tobe consistent with the applicable portions of ISO 6336-5:1996, to the extent possible whilethe two standards were in parallel developme
20、nt. The AGMA Technical Division ExecutiveCommittee approved the publication of AGMA 923-A00 in August, 2000.This edition of the information sheet, AGMA 923-B05, incorporates changes to item 8,microstructure, of table 1, Metallurgical characteristics for through hardened gearing. Thebalance of the do
21、cument remains unchanged. The AGMA Technical Division ExecutiveCommittee approved the publication of AGMA 923-B05 in May, 2005.Suggestions for improvement of this information sheet will be welcome. They should besent to the American Gear Manufacturers Association, 500 Montgomery Street, Suite 350,Al
22、exandria, Virginia 22314.AGMA 923-B05AMERICAN GEAR MANUFACTURERS ASSOCIATIONv AGMA 2005 - All rights reservedPERSONNEL of the AGMA Metallurgy and Materials CommitteeChairman: Phil Terry Lufkin Industries, Inc.Vice Chairman: Dale J. Weires Boeing Defense A is the cross sectional area of the cast ingo
23、tor continuous cast billet, in2(mm2).For bar stock and forged shafting including stepshafts for solid on shaft pinion blanks as in figure 5:B is the cross sectional area at the finishedlargest forging diameter in the area wherethe teeth will be, in2(mm2); and,C, D, E, F, G and H =1.For upset forged
24、gearing blanks as in figures 7 and 8:B is the cross sectional area of the billet priorto upsetting, in2(mm2);C is the height of the cutoff ingot prior to upset-ting, inch (mm);D is the height of the finish forged upset blankbefore piercing, inch (mm); andE, F, G and H =1.For forged or rolled rings:B
25、 is the cross sectional area of the billet priorto upsetting, in2(mm2);C is the height of the cutoff ingot prior to upset-ting, inch (mm);D is the height of the upset blank after upset-ting before piercing, inch (mm);E is the height of the upset blank after piercing,inch (mm);F is the wall thickness
26、 of the upset blank afterpiercing, before any bore expansionassociated with piercing, inch (mm);G is the height of the finish forged or rolled ring,inch (mm);H is the wall thickness of the finish forged orrolled ring, inch (mm).representative test coupon: A test coupon de-signed to represent the que
27、nching rate of thefinished gearing tooth. If the coupon is to be usedonly to determine the case properties, it can besmaller than one used to determine the coreproperties of the gear tooth. A representative testcoupon sized for determining the core hardness andmicrostructure can also be used for det
28、ermining thecase properties or as a process control test coupon.A representative test coupon sized for determiningthe case properties can also be used as a processcontrol test coupon but not for determining coreproperties unless substantiated by documented testdata. For procedures associated with re
29、presentativetest coupons, see 4.2.2.retained austenite: The metastable austeniteretained within a quenched microstructure. Theamount of retained austenite is a function of carboncontent, alloy content (especially nickel andmanganese), quench temperature and subsequentthermal or mechanical treatments
30、. See figures 11,12 and 13 for examples of visual estimates ofretained austenite (white constituent) in temperedmartensite. More precise measurements of retainedaustenite can be obtained by X-ray diffractiontechniques.shot peening: A cold working process performedby bombarding the surface of a part
31、with smallspherical media. This results in a thin layer of highmagnitude residual surface compressive stress andgenerally improves the bending strength in the rootsof gear teeth. Shot peening should not be confusedwith grit blasting or shot blasting which are cleaningoperations.AGMA 923-B05 AMERICAN
32、 GEAR MANUFACTURERS ASSOCIATION10 AGMA 2005 - All rights reserved5% nital etch 400X mag.Figure 11 - Tempered martensite and 5%retained austenite in carburized gearing5% nital etch 400X mag.Figure 12 - Tempered martensite and 20%retained austenite in carburized gearing5% nital etch 400X mag.Figure 13
33、 - Tempered martensite and 30%retained austenite in carburized gearingspecialty nitriding steel: A steel typically alloyedwith 1% aluminum to provide higher surface hard-ness after nitriding than normally attained withnitrided through hardening steels.standardized test coupon: Alternate terminologyf
34、or a process control test coupon.subcritical anneal: Reheating to a temperaturebelow the transformation range. For carburizedgearing the temperature is typically 1200-1250F(650-675C) and is done after carburizing andbefore hardening.surface hardening: The generic terminology forselective induction o
35、r flame heating of a surfacelayer and then quenching that layer to produce ahardened surface layer that may be thinner than theheated area, but is harder than the unheated basematerial. With induction or flame hardening there isno significant alteration of the chemical compositionof the surface laye
36、r.surface hardness: The hardness measureddirectly on the functional surface, after appropriatesurface preparation. Surface hardness is not to beconfused with case hardness, which is taken on aAGMA 923-B05AMERICAN GEAR MANUFACTURERS ASSOCIATION11 AGMA 2005 - All rights reservedmetallographic cross se
37、ction using a microhardnesstester.tempering: The reheating of a hardened ferrousalloy part to a temperature below the transformationrange, and then cooling it at any rate.test bar: A sample used for tensile or impactstrength testing. Also used as alternate terminologyfor a test coupon used for hardn
38、ess andmicrostructure testing.test coupon: See specific type of test coupon suchas process control or representative.total case depth: For carburized gearing themaximum depth of diffused carbon.The total case depth for induction or flame hardenedgearing is usually assumed to be the same as theharden
39、ed and effective case depths.The total case depth for nitrided gearing is thedistance from the surface to the depth at which theHRC hardness number is 110% of the hardnessnumber for the core.total nominal alloy content: The sum of themid-points of the specified ranges for all alloyingelements added
40、to increase hardenability (e.g., Mn,Cr, Ni, Mo).transformation temperature: The temperature atwhich a phase change occurs.traveling indication: An uninterrupted ultrasonictesting signal on the display which moves horizontal-ly on the sweep line as the transducer is moved onthe scanning surface. Trav
41、el of the signal indicatesvaried depth of the discontinuity from the scanningsurface, often indicative of a crack.4 Procedures4.1 Recommended test methodsThe test methods listed in this clause are to be usedwhen no other method is clearly defined or specified.These are the methods to be used for eva
42、luations tothe requirements of clause 5.Testing of the actual part is preferred and shouldalways be used whenever practical. However,properly selected test coupons can also be used.The dimensions in this document are always to bemeasured normal (not oblique) to the surface.Banding - See microsegrega
43、tion.Carbon - See surface carbon.Case hardnessFor carburize and hardened gearing, unlessotherwise specified, the case hardness is deter-mined at a location 1/2 of tooth height (or from arepresentative test coupon).For induction or flame hardened gearing, unlessotherwise specified, the case hardness
44、is deter-mined at a location 1/4 of tooth height above theroot.For nitrided gearing, unless otherwise specified,the case hardness is determined at a location 1/2of tooth height (or from a process control orrepresentative test coupon).Chemistry - Analyzed per ASTM A751.Core hardness - Per a standard
45、or superficialhardness testing method listed under “hardness”.Decarburization - Per any of three methods:Method 1 - File hardnessThe flanks of a tooth are file hardness tested perSAE J864 or ISO 6336-5, annex D with lack of filehardness indicating possible decarburization ornon-martensitic structure
46、s.Method 2 - Reduction of hardnessSurface hardness readings are taken in the samearea using two different hardness testing loads,such as HRC and HR15N with major loads of 150kg and 15 kg respectively. The two sets of read-ings are compared using a standard hardnessconversion chart, such as ASTM A370
47、, ASTME140 or ISO 6336-5, annex C. Decarburization isindicated by a lower converted hardness for thelighter load compared to that from the heavierload, presuming that proper hardness testingtechniques were used for both sets of tests.Method 3 - Metallographic evaluationA metallographic specimen is p
48、repared per ASTME3, etched per ASTM E407, and evaluated perASTM E1077 or SAE J419.Effective case depth - Per SAE J423 microhard-ness test method. For carburize and hardenedgearing and nitrided gearing, unless otherwisespecified, the effective case depth is determined at alocation 1/2 of tooth height
49、 (or from a representativetest coupon).For induction or flame hardened gearing, unlessotherwise specified, the effective case depth isAGMA 923-B05 AMERICAN GEAR MANUFACTURERS ASSOCIATION12 AGMA 2005 - All rights reserveddetermined at a location 1/4 of tooth height above theroot.Grain size - Per ASTM E112 or ISO 643.Hardenability - Per ASTM A255 or ISO 642end-quench test or by hardenability calculation perASTM A255.Hardness - Listed below are each method and theassociated processes which are tested by t
