(This Information Sheet is NOT an AGMA Standard). American Gear Metallurgical Specifications for Steel Gearing Manufacturers AGMA B05 CAUTION. (This Information Sheet is NOT an AGMA Standard). American Gear Metallurgical Specifications for Steel Gearing Manufacturers AGMA B05 Association. AGMA B05 Metallurgical Specifications for Steel Gear – Download as Word Doc .doc /.docx), PDF File .pdf) or read online. AGMA B05 Metallurgical.
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Process control test coupons are not intended to be used for final acceptance. Figure 7 shows the calculated mean-free paths for the globular oxide inclusions greater than 10 mm in square root area and stringers longer than mm in length. For induction or flame hardened gearing, alternative terminology for effective case depth.
Quantitative stereography can be employed to convert the measured area concentration of inclusions to mean-free path between inclusions and volumetric concentration, enabling the gear design engineer to make direct comparisons of stressed volumes and volumetric inclusion concentrations.
A heat treatment process in which an austenitized steel is brought into contact with a carbonaceous atmosphere of sufficient carbon potential to cause adsorption of carbon at the surface and by diffusion to create a concentration gradient. Method 2 — Combustion The combustion method utilizes chips from a machining cut of 0. A segregated structure consisting of alternating, nearly parallel bands of different chemical composition, typically aligned in the direction of primary hot working.
At this time, the Ultrapremium practice and certification limits with steels are produced using bottom-poured ingots. We have no amendments or corrections for this standard. The amount of retained austenite is a function of carbon content, alloy content especially nickel and manganesequench temperature and subsequent thermal or mechanical treatments.
Once the worst 0. When ultrasonic inspection is specified, the following guidelines shall apply: Variations from expected process control limits are used as indicators of unacceptable heat treat process variations. Characterization of the inclusion population for a heat of steel requires tens of hours of SEM run time, but only tens of minutes of sample preparation and operator time.
Gear Design Relevant Cleanness Metrics
These data can quickly be considered with respect to a gear size or a test coupon size to get a sense of the probability of inclusion-related fatigue failures. The properties of a process control coupon may be correlated by experience to the properties of the finished gearing with regard to hardness and case depth.
Table 2 – Metallurgical characteristics for carburize and hardened gearing Item Characteristic1 2 1 Material chemistry 2 3 4 Grain size Hardenability Non–metallic inclusions cleanliness, steelmaking 3 4 Grade 1 Specified, but not verified. The outer portion that has been made harder than the inner portion see core hardness as a result of altered composition, microstructure, or both, by treatments such as carburize and hardening, induction hardening, flame hardening, and nitriding.
Nitrided The effective case depth is measured from the finished surface to a location where the hardness number is equivalent to Please first verify your email before subscribing to alerts. Mechanical properties prior to case hardening. The microstructure in this zone should be predominantly tempered martensite.
Magnetic particle inspection of Inspection recommended to the Inspection required to the following finished gearing 7 20 21 22 following limits: Suggestions for improvement of this standard will be welcome. For example an actual microhardness test reading of HK has a converted hardness of 50 HRC and would be properly reported as 50 HRC HK with the hardness number and scale in parentheses representing the actual testing result and method.
Method 1 — File hardness The flanks of a tooth are file hardness tested per SAE J or ISOannex D with lack of file hardness indicating possible decarburization or non–martensitic structures.
Induction, flame, and nitride hardened gearing may use the term base hardness. Quantity must be a positive whole number. For induction or flame hardened gearing, unless otherwise specified, the effective case depth is 4 Procedures 4.
Other mechanical testing is required only if specified. Below this zone the core microstructure should be free of blocky ferrite and be primarily tempered martensite with some acicular ferrite and bainite permissible.
This can be accomplished by specifically certifying each requirement where necessary, or by establishing practices and procedures to 923-h05 the requirements on a production basis.
For nitriding specifications 923-bb05 hardness is typically used rather than case hardness. For procedures associated with process control test coupons, see 4. Any of the following methods are acceptable Should meet the following surface related characteristic: Log in to leave a comment.
Microstructure – See metallography. This process is repeated for each stringer inclusion type A, B, C. Non–martensitic struc- martensite with no non–martensitic rating. A minimum hardenability verified by certification, calculation or test which is appropriate for part size and quench severity should be specified.
All standards are subject to revision, and parties to agreements based on this document are encouraged to investigate the possibility of applying the most recent editions of the standards shown below. An aggregate of ferrite and cementite resulting from the transformation of austenite at temperatures below the pearlite range but above the martensite start temperature.
See figures 11, 12 and 13 for examples of visual estimates of retained austenite white constituent in tempered martensite. A wide range of agmq geometric measures can be selected as needed. In each agja, the Z-contrast of these particles against the steel matrix makes them readily detectable. See figures 1 through 4 for photomicrographs of various classifications of carbide structures white constituent afma tempered martensite.
In the rating method called out in ASTM E45 Method A, an operator uses a light optical microscope to scan the polished surface of a specimen at times magnification looking for the worst field for each agmw four inclusion types, with thin and heavy categories for each type. Strength and quality of materials ISO The term core hardness is applicable to carburize and hardened gearing.
AGMA B05 – Metallurgical Specifications for Steel Gearing
The metastable austenite retained within a quenched microstructure. The reduced variate is a log-log measure of the accumulated inspected area over the set of extreme value samples.
The sensitivity for the flat bottom hole method shall utilize standard test blocks per ASTM E with the reflector size as specified in 9223-b05 1 through 4 of this information sheet. The Ultrapremium practice for its strand cast process path is under development.
Acceptance criteria is not specified but is to be agreed upon.