Mechanical and Material Requirements for Metric Externally Threaded Steel Fasteners
公制外螺纹钢制紧固件机械性能与材料要求
1. Scope 范围
1.1 This SAE Standard covers the mechanical and material requirements for eight property classes of steel, externally threaded metric fasteners in sizes M1.6 through M36, inclusive, and suitable for use in automotive and related applications.
本SAE 标准涵盖汽车及相关工业使用，尺寸在M1.6到M36钢铁外螺纹紧固件的八个性能等级的机械性能与材料要求。
1.2 Products included are bolts, screws, studs, U-bolts, preassembled screw and washer assemblies (sems), and products manufactured the same as sems except without washer.
产品包括：螺栓、螺钉、螺柱、U型螺栓、预装配的螺钉和垫片组件以及与预装配组件一样加工的无垫圈产品。
1.3 Products not covered are tapping screws, thread-rolling screws, and self-drilling
screws. Mechanical and material requirements for these products are covered in other SAE documents.
产品不包括自攻螺钉、自挤螺钉、钻尾螺钉。这些产品的机械性能与材料要求包含在SAE另外的标准中。
1.4 The term stud as referred to herein, applies to a cylindrical rod of moderate length, threaded on either one or both ends or throughout its entire length. It does not apply to headed, collared, or similar products which are more closely characterized by requirements shown herein for bolts. 螺柱这里是指适用于中等长度圆柱杆，螺纹在一端有或两端都有，或全螺纹的产品。它并不适用于有头的、带定位的或类似于本文中所要求的螺栓特性近似的产品。
1.5 For specification purposes, this document treats U-bolts as studs. Thus, wherever the word studs appears, U-bolts is also implied. U-bolts covered by this document are those used primarily in the suspension and related areas of vehicles. (Designers should recognize that the U
configuration may not sustain a load equivalent to two bolts or studs of the same size and grade; thus actual load-carrying capacity of U-bolts should be determined by saddle load tests.)
为了规范，本标准将U型螺栓是为螺柱。因此，本文中涉及到的螺柱要求，U型螺栓同样适用。本文所提及的U型螺栓是使用于车辆悬挂位置或相关位置的产品。（设计者应了解到同样尺寸、等级的U型螺栓与两个螺栓或螺柱的载荷是不相等的，因此，U 型螺栓的实际承载应以鞍型荷重测试方法来判定。
2 References 参考资料
2.1 Applicable Publications — The following publications form a part of this specification to the extent specified herein. Unless otherwise indicated, the latest issue of SAE publications shall apply.
适用版本- 下列出版物作为本标准的一部分。除非另有规定，应采用SAE最新版本标准。
2.1.1 SAE PUBLICATIONS — Available from SAE, 400 Commonwealth Drive, Warrendale, PA 15096-0001.
SAE 美国汽车工程协会出版物
SAE J121M—Decarburization in Hardened and Tempered Metric Threaded Fasteners
公制螺纹紧固件淬硬和回火的脱碳要求
SAE J123—Surface Discontinuities on Bolts, Screws, and Studs in Fatigue Applications
用于疲劳载荷的螺栓、螺钉及螺柱的表面不连续性
SAE J429—Mechanical and Material Requirements for Externally Threaded Fasteners
外螺纹紧固件的机械性能及材料要求
SAE J1061—Surface Discontinuities on General Application Bolts, Screws, and Studs
通用螺栓、螺钉及螺柱的表面不连续性
2.1.2 ASTM PUBLICATIONS — Available from ASTM, 100 Barr Harbor Drive, West Conshohocken, PA 19428-2959.
ASTM 美国材料与试验协会出版物
ASTM A 307—Specification for Carbon Steel Bolts and Studs, 60 000 psi Tensile 抗拉强度 60kpsi碳钢螺栓、螺柱的相关规范要求
ASTM A 354—Specification for Quenched and Tempered Alloy Steel Bolts, Studs, and Other Externally Threaded Fasteners
淬火和回火合金钢螺栓、螺柱和其他外螺纹紧固件的标准规范
ASTM A 449—Specification for Quenched and Tempered Steel Bolts and Studs
淬火和回火钢制螺栓及螺柱的标准规范
ASTM F 606M—Standard Test Methods for Determining the Mechanical Properties of Externally and Internally Threaded Fasteners, Washers, and Rivets
测定外螺纹及内螺纹紧固件、垫圈及铆钉的机械特性的试验方法(米制)
2.1.3 ASME PUBLICATION — Available from ASME, 345 East 47 Street, New York, NY 10017-2330.
ASME 美国机械工程师协会出版物 ASME B18.2.1
3. Designations 标示
3.1 Property classes are designated by numbers where increasing numbers generally represent increasing tensile strengths. The designation symbol consists of two parts:
性能等级由数字标示，数字越大通常代表抗拉强度越大。标示符号由两部分组成： a. The first numeral of a two-digit symbol or the first two numerals of a three-digit symbol approximates 1/100 of the minimum tensile strength in MPa.
二个数字符号的第一个数或三个数字符号的前两位数接近最小抗拉强度（MPa）的1/100。 b. The last numeral approximates 1/10 of the ratio expressed as a percentage between minimum yield stress and minimum tensile stress.
最后一个数字约1/10的比率表示为最小屈服强度与最小抗拉强度指间的百分比。 3.2 For specification purposes (on engineering drawings, purchase orders, etc.) all property class designations are used in combination with a single basic specification number as follows: 为了规范（在工程图、采购订单等文件中），所有性能等级标示使用由单个基本规范的数字组合，如下所示： SAE J1199 (4.6) SAE J1199 (4.8)
SAE J1199 (5.8) SAE J1199 (8.8) SAE J1199 (9.8) SAE J1199 (10.9)
3.3 Property Classes 性能等级
3.3.1 Machine screws are normally available only in classes 4.8 and 9.8; other bolts, screws, and studs are available in all classes within the specified product size limitations given in Tables 1A and 1B.
机械螺钉通常仅适用于4.8级和9.8级；其他螺栓、螺钉和螺柱适用于表1A和表1B所规定所有等级。
3.3.2 Screw and washer assemblies (sems) are covered by classes 4.8 and 9.8 and allowable deviations from normal 9.8 requirements are stated in footnotes throughout the document. 螺钉和垫片组件涵盖在4.8级和9.8级中，偏离正常9.8级的允差要求在整篇文档有脚注。
3.3.3 At the option of the manufacturer, class 5.8 may be supplied with either class 4.6 or 4.8 is ordered, and class 4.8 may be supplied when class 4.6 is ordered.
供应商可自行选择：4.6级或4.8级订单产品可按5.8级提供；4.6级订单产品可按4.8级提供。
3.4 Conversion Guidance 转换指导
3.4.1 For guidance purposes only, to assist designers in selecting a property class: 仅为引导目的，以协助设计者选着性能等级：
a. Class 4.6 is approximately equivalent to SAE J429, Grade 1 and ASTM A 307, Grade A.
4.6级性能强度近似于SAE J429 等级1和ASTM A307 等级A的性能强度 。 b. Class 5.8 is approximately equivalent to SAE J429, Grade 2.
5.8级性能强度近似于SAE J429 2级的性能强度。
c. Class 8.8 is approximately equivalent to SAE J429, Grade 5, and ASTM A 449.
8.8级性能强度近似于SAE J429 5级和ASTM A 499的性能强度。
d. Class 9.8 has properties approximately 9% stronger than SAE J429, Grade 5, and ASTM A 449.
9.8级机械性能强度比SAE J429 5级和ASTM A 499 的强度高约9%。
e. Class 10.9 is approximately equivalent to SAE J429, Grade 8, and ASTM A 354, Grade BD.
10.9级性能近似于SAE J429 8级和ASTM A 354 BD级的性能强度。
表 1A—螺栓、螺钉和螺柱的机械性能要求 全尺寸产品保性能等级 4.6 4.8 5.8 8.8 9.8 10.9 1. 2. 3. 4. 5. 公称直径 M5到M36 M1.6到M16 M5到M24(4) M17到M36 M1.6到M16（5） 全尺寸产品最小抗拉强度Mpa(1) 加工试样产品（尺寸大于M24）最小屈服强度Mpa 240(3) - - 660 - 940 加工试样产品（尺寸＞M24）最小抗拉强度Mpa400 - - 830 - 1040 （2） 加工试样产品（尺寸＞M24）最小伸长率% 22 - - 12 - 9 加工试样产品（尺寸＞M24）最小端面收缩率% 35 - - 35 - 35 证载荷Mpa225 310 380 600 650 830 (1) 400 420 520 830 900 1040 M6到M36 全尺寸产品每一性能等级的保证载荷及抗拉强度值见表5。 屈服强度是应力发生在 0.2%的永久变形的量具长度计算所得的应力。 屈服点适用于替代屈服强度在0.2%偏移量的4.6级产品。 5.8级适用于产品长度≤150mm的螺栓及螺钉，以及所有长度的螺柱。 对于9.8级的螺钉与垫片组件产品，基材硬度可在25-40HRC(270-390HV)之间，表面硬度不能超过60 HR30N. 此要求同样适用于和组件一样加工的无垫片，尺寸在M1.6到M12的产品。 表 1B—螺栓、螺钉和螺柱的机械性能要求 性能等级 4.6 4.8 5.8 8.8 9.8 10.9 1. 2. 3. 4. 公称直径 M5到M36 M1.6到M16 M5到M24(2) M17到M36 M1.6到M16（4） 最大表面洛氏硬度30N- - - （3） （3） （3） 产品洛氏硬度最小B67 B71 B82 C23 C27 C33 （1） 产品洛氏硬度最大 B87 B87 B95 C34 C36 C39 产品维氏硬度最小（1） 产品维氏硬度最大 180 180 220 336 354 382 120 130 160 254 279 327 M6到M36 如果最小抗拉强度满足要求，最小硬度值不予要求。 5.8级适用于产品长度≤150mm的螺栓及螺钉，以及所有长度的螺柱。 表面硬度不得超过多于两点测得的基材硬度（洛氏C相当），10.9级情况下也不得超过59 HR30N. 对于9.8级的螺钉与垫片组件产品，基材硬度可在25-40HRC (270-390HV)之间，表面硬度不能超过60 HR30N. 此要求同样适用于和组件一样加工的无垫片，尺寸在M1.6到M12的产品。
3.4.2 Note that class 8.8 is applicable to sizes above 16 mm, and class 9.8 is applicable to sizes 16 mm and smaller.
8.8级适用于尺寸大于16mm的产品，9.8适用于尺寸≤16mm的产品。
4 Materials and Processes 材料及流程
4.1 Steel Characteristics—Bolts, screws, and studs shall be made of steel conforming to the
description and chemical composition requirements specified in Table 2 for the applicable property class.
钢材特性- 螺栓、螺钉和螺柱材料应符合表2中各相应等级的相关说明及化学成分要求。 性能等级 4.6和4.8 5.8 说明与化学成分 供应商自选-低、中碳钢（所有尺寸），成分要求：C:≤0.55、P:≤0.048，S:≤0.058 供应商自选-低、中碳钢（所有尺寸），成分要求：C:0.13-0.55、P:≤0.048，S:≤0.058; 仅对螺柱: S:≤0.33 供应商自选- 中碳钢（所有尺寸），成分要求：C:0.28-0.55、P:≤0.048，S:≤0.058，仅对螺柱: S:≤0.13； 8.8 中碳合金钢（尺寸＞M24），成分要求：C:0.28-0.55、P:≤0.040，S:≤0.045； 客户指定材料- 低碳马氏体钢（尺寸≤M20）, 成分要求：C:0.15-0.27, Mn:0.74-1.46, P:≤0.038, S:≤0.048, B:0.0005-0.003(1); 中碳硼钢（尺寸≤M24）, 成分要求：C:0.25-0.40, Mn:≥0.74 P:≤0.048, S:≤0.058, B:0.0005-0.003(1); 供应商自选- 中碳钢（所有尺寸），成分要求：C:0.28-0.55, P:≤0.048, S:≤0.058; 仅对螺柱: S:≤0.13； 9.8 对螺钉与垫片组件产品以及和组件一样加工的无垫片产品，尺寸≤M12，碳含量可0.15-0.40，见表6 注2； 客户指定材料- 低碳马氏体钢（尺寸≤M20）, 成分要求：C:0.15-0.27, Mn:0.74-1.46, P:≤0.038, S:≤0.048, B:0.0005-0.003(1); 中碳硼钢（尺寸≤M24）, 成分要求：C:0.25-0.40, Mn:≥0.74 P:≤0.048, S:≤0.058, B:0.0005-0.003(1); 供应商自选- 中碳合金钢（所有尺寸），成分要求：C:0.28-0.55, P:≤0.040, S:≤0.045, 细晶粒; 淬硬性≥47HRC(2) SAE 1541 或 SAE 1541 H (尺寸≤M12), 细晶粒； 10.9 客户指定材料- 碳钢（尺寸≤M20）,细晶粒； 低碳马氏体钢（尺寸≤M20）,成分要求：C:0.15-0.27, Mn:0.74-1.46, P:≤0.038, S:≤0.048, B:0.0005-0.003(1), 淬硬性≤40HRC(2); 中碳硼钢（尺寸≤M24）, 成分要求：C:0.25-0.40, Mn:≥0.74 P:≤0.048, S:≤0.058, B:0.0005-0.003(1), 淬硬性≤40HCR(2)。 1. 由低碳马氏体钢和中碳硼钢制造的产品须按照表6注1的要求进行标识识别。 2. 钢材须有淬硬性，淬硬性能产生最小硬度值（洛氏硬度C）,此硬度测与螺栓、螺钉或螺柱（淬火后）螺纹端一个公称直径横切面的中心位置。
4.2 Heading practice 头部成型
4.2.1 Methods other than upsetting and/or extrusion are permitted only by special agreement between purchaser and manufacturer.
有别于一般镦锻成型或挤压成型以外的成型方式需经过买卖双方同意方可执行。
4.2.2 Class 4.6 may be hot or cold headed at option of the manufacturer. 4.6级的产品用热锻或冷锻，由制造方决定。
4.2.3 Class 4.8, 5.8, 8.8, 9.8, and 10.9 bolts and screws in sizes up to M20 inclusive, and lengths