1、ANSI H35.3-2017Revision of H35.3-1997 (R2013)1. Scope1.1 This standard provides a system for des-ignating aluminum hardeners used primarily for the addition of alloying or grain re ning ele-ments or modi ers to aluminum alloy melts.2. Aluminum Hardener Designation System2.1 This system consists of f
2、our digit numeri-cal designations pre xed by the letter H. The rst two digits identify the aluminum hardener group by major alloying element as shown in Table 1. The last two digits indicate the se-quential registration of aluminum hardeners beginning with number H2X00 and have no other signi cance.
3、TABLE 1Designations for Aluminum Hardener GroupsMajor Alloying Designation Elements No.Other Elements(a) H20XXCu H21XXAluminum Hardeners Ti, B H22XXGrouped by Si H23XXMajor Added Mn H24XXElements Ni H25XXOther Than Zr, V H26XXAluminum Two or more elements, H27XXeach over 9.5%Fe H28XXCr H29XX(a) Majo
4、r elements other than those listed.American National StandardDesignation System for Aluminum HardenersApproved July 12, 2017 Secretariat: The Aluminum Association, Inc.Chemical composition limits and designations conforming to this standard may be registered with the Aluminum Association provided (a
5、) the aluminum hardener is offered for sale; (b) the aluminum hardener contains more aluminum than attributableto impurity and the aluminum serves a useful function other than qualifying the aluminum hardener for inclusion in the system;(c) the aluminum hardener must be produced speci cally for and
6、regularly used as an alloying material in the production of aluminum and aluminum alloys;(d) the complete chemical composition limits are registered; and(e) the composition is signi cantly different from that of any other aluminum hardeners for which a numerical designation already has been assigned
7、, where “signi cant” is de ned as:(i) A change of the following amounts or more in arithmetic mean of the limits for each individual alloying element:Arithmetic Mean of Minimum Arithmetic Limits for Alloying Changes Need for Elements in Registered New Aluminum Hardener Aluminum Hardener Issuance*Up
8、thru 0.30 percent 0.10Over 0.30 thru 1.0 percent 0.15Over 1.0 thru 2.0 percent 0.20Over 2.0 thru 3.0 percent 0.30Over 3.0 thru 4.0 percent 0.40Over 4.0 thru 5.0 percent 0.50Over 5.0 thru 6.0 percent 0.70Over 6.0 1.00*Lesser amounts are considered too small to issue new aluminum hardener designation.
9、(ii) Addition or deletion of one or more alloying elements with limits having an arithmetic mean of 0.20 percent or more. (iii) Change in limits for impurities for which the difference between arithmetic means (existing and proposed) is at least 0.10 percent. For codi cation purposes an alloying ele
10、ment is any element which is intentionally added. A major element is that element other than aluminum having the greatest nominal concentration. Should two or more major elements have equal nominal concentrations, that element appearing rst in the element limit sequence shall be used to determine de
11、signation grouping. When nominal concentration of two or more elements are each greater than 9.5%, such aluminum hardeners are assigned to the 27XX group. Standard limits for alloying elements and impurities are expressed in the following sequence: Silicon; Iron; Copper; Manganese; Chromium; Nickel;
12、 Titanium; Boron; Vanadium (See Note 1); Other (See Note 2) elements, Each; Other (See Note 2) elements, Total; Aluminum (See Note 3).Note 1 Additional speci ed elements having limits are inserted in alphabetical order by their chemical symbols between Vanadium and Other Elements, Each, or are speci
13、 ed in footnotes.Note 2 “Others” includes listed elements for which no speci c limit is shown as well as unlisted metallic elements. “Total is the sumof those “Others” metallic elements 0.010 or more each, expressed to the second decimal before determining the sum. The producer may analyze samples f
14、or trace elements not speci ed in the registration or speci cation; however, such analysis is not required and may not cover all metallic “Others” elements. Should any analysis by the producer or the purchaser establish that an “Others” element exceeds the limit of “Each” or that the aggregate of se
15、veral “Others” elements exceeds the limit of “Total”, the material shall be considered non-conforming.Note 3 Aluminum is speci ed as a remainder for aluminum hardeners.An American National Standard implies a consensus of those substantially concerned with its scope and provisions. An American Nation
16、al Standard is intended as a guide to aid the manufacturer, the consumer, and the general public. The existence of an American National Standard does not in any respect preclude anyone, whether he has approved the standard or not, from manufacturing, marketing, purchasing, or using products, process
17、es, or procedures not conforming to the stan-dard. American National Standards are subject to periodic review and users are cautioned to obtained the latest editions.The American National Standards Institute does not develop standards and will in no circumstances give an interpretation of any Americ
18、an National Standard. More-over, no person shall have the right or authority to issue an interpretation of an American National Standard in the name of the American National Standards Institute.CAUTION NOTICE: This American National Standard may be revised or withdrawn at any time. The procedures of
19、 the American National Standards Institute require that action be taken to rea rm, revise, or withdraw this standard no later than ve years from the date of approval. Purchasers of American National Standards may receive current information on all standards by calling or writing the American National Standards Institute. Copyright 2017, The Aluminum Association, Inc. All rights reserved. Unauthorized reproduction, distribution, creation of derivative works, and/or sale of this work is prohibited.Changes are indicated by highlights in the text
