标准编号:	GB/T 229-2020
中文名称:	金属材料 夏比摆锤冲击试验方法
英文名称:	Metallic materials—Charpy pendulum impact test method
中标分类:	H22    金属力学性能试验方法
行业分类:	GB    国家标准
ICS分类:	77.040.10 77.040.10    金属材料力学试验 77.040.10
发布机构:	国家市场监督管理总局 国家标准化管理委员会
发布日期:	2020-09-29
实施日期:	2021-4-1
标准状态:	valid
替代旧标准:	GB/T 229-2007 金属材料 夏比摆锤冲击试验方法
翻译语言:	英文
文件格式:	PDF
中文字符数:	27000 字
翻译价格(元):	1800.0
交付时间:	付款后 1 个工作日

This standard is developed in accordance with the rules given in GB/T 1.1-2009. This standard replaces GB/T 229-2007 Metallic materials - Charpy pendulum impact test method, and the following main technical changes have been made with respect to GB/T 229-2007: - notch-free test pieces are added in the scope, and requirements are made for terms and definitions, symbols and interpretation, dimensional deviation and test piece installation (see Clause 1, 3.2.1, Table 1, Table 2, 8.1 and Annex A); - some of the terms and definitions are modified and added (see 3.1.3, 3.2.1, 3.2.2 of this standard, and 3.2.1 and 3.2.2 of 2007 edition); - symbol B of sample thickness, angle symbol α when pendulum is released, explanation of angles of rise β1 and β2, symbol KN of nominal initial potential energy, symbol M of torque, symbol ρ of energy loss caused by pointer friction, symbol ρ' of energy loss caused by bearing friction and air resistance, and correction symbol ρβ of energy loss caused by angle of rise β are added, and symbol of shear fracture appearance is changed to SFA. The symbol of transition temperature symbol Tt27 corresponding to the specified absorbed energy value of 27 J, transition temperature symbol Tt50% us corresponding to 50% absorbed energy of the upper shelf, transition temperature symbol Tt50%SFA corresponding to 50% shear fracture and transition temperature symbol Tt0.9 corresponding to lateral expansion 0.9 mm are added (see table 1 of this standard, and that of 2007 edition); - the principle of impact test is added (see Clause 5 of this standard and Clause 5 of 2007 edition); - the determination of friction loss is added (see 8.2); - the requirements of test temperature are added (see 8.3.3 of this standard, and 8.2.3 of 2007 edition); - mandatory information and optional information are added in the test report [see 9.1 g), 9.2 j) and k)]; - informative Annex E “Measurement uncertainty of an absorbed energy value, K” (see Annex E) is added; - the informative Annex about high temperature or low temperature compensation value is deleted (see Annex E of 2007 edition). This standard has been redrafted and modified in relation to IEC 148-1:2016 Metallic materials - Charpy pendulum impact test - Part 1: Test method Compared with ISO 148-1: 2016, there are structural differences in this standard, with 8.9 test results added. There are some technical differences between this standard and ISO 148-1:2016, which are marked with perpendicular single line (｜) in the outside page margin of the provisions concerned. The technical differences and their causes are as follows: —— In Clause 1, notch-free test pieces are added to adapt to China's national conditions; ——the adjustments of technical differences are made for the normative references in this standard so as to adapt to the technical conditions of China. The adjustments are mainly reflected in Clause 2 "Normative references", which are shown in the following:  ISO 148-2 is replaced by GB/T 3808, which is modified in relation to the international standard (see 7.2 and E.2.1.2);  GB/T 2975 is added for reference (see 6.4);  GB/T 8170 is added for reference (see 8.9);  JJG 145 is added for reference (see 7.2);  ISO 268-1 is deleted (see Table 2 of ISO 148 -1). - The symbol KT and its interpretation missing in ISO standard are added in Table 1, and the symbol and interpretation of notch-free test pieces are correspondingly as notch-free test pieces are added in the scope. The unit of β1 and β2 is defined as "°", and the unit of K1, K2 and KN is defined as "J" to avoid confusion. - the last two paragraphs of Clause 5 are changed to notes, because they further explain the principle; - “And test pieces with other thicknesses may also be used upon agreement.” is added in 6.1.2 to expand the applicable scope of this standard;   - “The samples shall be cut according to relevant product standards or GB/T 2975.” is added in 6.4 to facilitate practical operation; - in Table 2, the dimensions and tolerances of U-notch test piece with ligament width of 8 mm are added, the notes of notch-free test pieces were added, the included angle tolerance between adjacent longitudinal faces of test pieces is adjusted, and the tolerance grades of two kinds of notches are deleted to meet the national conditions of China; - for the convenience of application, the symbols KW2 and KW8 for the striking edge of the notch-free test piece pendulum are added in 7.3; - for the convenience of operation of notch-free test pieces, the provisions on the installation position of notch-free test pieces and the inspection before the test are added in 8.1; - the detailed requirements on bearing friction and wind resistance loss are added in 8.2.2 for the implementation of this standard; - the requirements of the lower limit of use and resolution of the testing machine are added in 8.5, and Note 2 is added to explain, so as to increase the operability of the standard and facilitate the implementation of this standard; - the explanation “If the pendulum does not break the sample, and the measured absorbed energy exceeds the energy range of the testing machine due to insufficient impact energy of the testing machine” is added in 8.6 to increase the operability of this standard. - the rounding off requirements of absorbed energy is added in 8.9, and increase the operability of this standard; - c) notch type and ligament width (notch depth) is added in 9.1, and the requirements of sample size expression are added in d) to increase the operability of this standard; - in Annex A, the sentence "self-centring tongs with thickness of 5 mm and 3 mm” are deleted due to data error; and the requirements of tongs for notch-free test pieces and U-notch tongs are added to increase the operability of this standard and facilitate the implementation of this standard. The following editorial changes have been made in this standard: - the standard name is changed; - the expression "the letter W is used to indicate notch-free test piece" is added in the note of 3.1.2. This standard was proposed by China Iron and Steel Association. This standard is under the jurisdiction of SAC/TC 183 National Technical Committee on Iron and Steel of Standardization Administration of China. The previous editions of standard replaced by this standard are as follows: ——GB/T 229-1984, GB/T 229-1994, GB/T 229-2007. Metallic materials - Charpy pendulum impact test method 1 Scope This standard specifies the Charpy (V-notch and U-notch) pendulum impact test method for determining the energy absorbed in an impact test of metallic materials. This standard is applicable to Charpy pendulum impact test at room temperature, high temperature or low temperature, but does not cover instrumented impact testing, which is specified in GB/T 19748. 2 Normative references The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. GB/T 2975 Steel and steel products - Location and preparation of samples and test pieces for mechanical testing (GB/T 2975-2018, ISO 377:2017, MOD) GB/T 3808 Verification of pendulum-type impact testing machines (GB/T 3808-2018, ISO 148-2: 2008, MOD) GB/T 8170 Rules of rounding off for numerical values & expression and judgment of limiting values JJG 145 Verification regulation of pendulum impact testing machines 3 Terms and definitions For the purposes of this document, the following terms and definitions apply. 3.1 Definitions pertaining to energy 3.1.1 initial potential energy potential energy Kp potential energy of the pendulum hammer prior to its release for the impact test, as determined by direct verification 3.1.2 absorb energy K energy required to break a test piece with a pendulum impact testing machine, after correction for friction Note: The letter V or U is used to indicate the notch geometry, the letter W is used to indicate notch-free test piece. The number 2 or 8 is used as a subscript to indicate the radius of the striker, for example KV2. 3.1.3 nominal initial potential energy nominal energy KN energy assigned by the manufacturer of the pendulum impact testing machine 3.2 Definitions pertaining to test piece 3.2.1 width W distance between the notched face and the opposite face Note 1: For notch-free test piece, it is the distance between the surface where the strike center is located and its opposite surface. Note 2: See Figure 1. Note 3: In GB/T 229-2007, the distance between the notched face and the opposite face was specified as “height”. Changing this dimension to “width” makes this standard consistent with the terminology used in other fracture standards. 3.2.2 thickness B dimension perpendicular to the width and parallel to the notch Note 1: For notch-free test piece, it is the minimum dimension perpendicular to the width direction. Note 2: See Figure 1. Note 3: In GB/T 229-2007, the dimension perpendicular to the width direction and parallel to the notch axis was specified as “width”. Changing this dimension to “thickness” makes this standard consistent with the terminology used in other fracture standards. 3.2.3 length L largest dimension perpendicular to the notch Note 1: For notch-free test piece, it is the maximum dimension perpendicular to the width direction. Note 2: The notch direction is the notch depth direction, as shown in Figure 1. Key 1——anvil; 4——shroud; 7——thickness of test piece, B; 2——standardized test piece; 5——width of test piece, W; 8——centre of strike; 3——test piece supports; 6——length of test piece, L; 9——direction of pendulum swing. Note: The shroud may be used in U-shaped pendulum testing machine to protect the broken test piece from rebounding to the pendulum and jamming. Figure 1 Relative position of test piece to the supports and anvils of a pendulum impact testing machine 4 Symbols and interpretations The symbols and interpretations applicable to this standard are indicated in Table 1.   Table 1 Symbols, designation and unit Symbol Unit Designation B mm thickness of test piece α ° angle of fall of the pendulum β1 angle of rise in the fall of the pendulum without a test piece in position β2 angle of rise in the fall of the pendulum without a test piece in position and without resetting the indication mechanism L mm length of test piece LE mm lateral expansion K J absorbed energy (expressed as KV2, KV8, KU2, KU8, to identify specific notch geometries and the radius of the striking edge) J indicated absorbed energy in the fall of the pendulum without a test piece in position K2 J indicated absorbed energy in the fall of the pendulum without a test piece in position and without resetting the indication mechanism KN J nominal initial potential energy Kp J initial potential energy (potential energy) KT J total absorbed energy KV2 J absorbed energy for a V-notch test piece using a 2 mm striker KV8 J absorbed energy for a V-notch test piece using a 8 mm striker KU2 J absorbed energy for a U-notch test piece using a 2 mm striker KU8 J absorbed energy for a U-notch test piece using a 8mm striker KW2 J absorbed energy for a notch-free test piece using a 2 mm striker KW8 J absorbed energy for a notch-free test piece using a 8mm striker M N·m moment equal to the product F·l2 ρ J absorbed energy loss caused by pointer friction ρ′ J absorbed energy loss caused by bearing friction and air resistance ρβ J correction of absorbed energy losses for an angle of rise β SFA % shear fracture appearance Tt ℃ transition temperature W mm width of test piece Tt27 ℃ transition temperature defined at a specific value of absorbed energy; for example, 27 J Tt50%US ℃ transition temperature defined at a particular percentage of the absorbed energy of the upper shelf; for example, 50 % Tt50%SFA ℃ transition temperature defined at a particular proportion of shear fracture; for example, 50 % Tt0.9 ℃ transition temperature defined at a particular amount of lateral expansion; for example, 0.9 mm   5 Principles of the test This test consists of breaking a test piece with a single blow from a swinging pendulum, under the conditions defined in Clauses 6, 7 and 8. The notch in the test piece has a specified geometry and is located in the middle between two supports, opposite to the location which is impacted in the test. The energy absorbed in the impact test, the lateral expansion and the shear fracture appearance are normally determined. Because the impact values of many materials vary with temperature, tests shall be carried out at a specified temperature. When this temperature is other than ambient, the test piece shall be heated or cooled to that temperature, under controlled conditions. Note 1: The Charpy pendulum impact test is often used in routine, high-throughput pass/fail acceptance tests in industrial settings. For these tests, it may not be important whether the test sample is completely broken, partially broken, or simply plastically deformed and dragged through the anvils. In theoretical research, the measured energy values shall be studied in more detail, in which case it can be highly relevant whether the sample is broken or not. Note 2: It is important to note that not all Charpy pendulum impact test results can be directly compared. For example, the test can be performed with hammers having strikers with different radii, or with different test piece shapes. Tests performed with different strikers can give different results.[2] This is why not only the adherence to this standard but also a clear and complete reporting of the type of instrument, the test piece and the details of the post-test test pieces are crucial for comparability of results.

Foreword I 1 Scope 2 Normative references 3 Terms and definitions 3.1 Definitions pertaining to energy 3.2 Definitions pertaining to test piece 4 Symbols and interpretations 5 Principles of the test 6 Test pieces 6.1 General 6.2 Notch geometry 6.3 Tolerance of the test pieces 6.4 Preparation of the test pieces 6.5 Marking of the test pieces 7 Test equipment 7.1 General 7.2 Installation and verification 7.3 Striker 8 Test procedure 8.1 General 8.2 Friction measurement 8.3 Test temperature 8.4 Specimen transfer 8.5 Machine capacity 8.6 Incomplete fracture 8.7 Test piece jamming 8.8 Post-fracture inspection 8.9 Test result 9 Test report 9.1 Mandatory information 9.2 Optional information Annex A (Informative) Self-centring tongs Annex B (informative) Lateral expansion Annex C (Informative) Fracture appearance Annex D (Informative) Absorbed energy vs. temperature curve and the transition temperature Annex E (Informative) Measurement uncertainty of an absorbed energy value, K Bibliography

金属材料 夏比摆锤冲击试验方法 1 范围 本标准规定了金属材料在冲击试验中测定冲击试样(V型、U型缺口和无缺口试样)吸收能量的夏比摆锤冲击试验方法。 本标准适用于室温、高温或低温条件下夏比摆锤冲击试验，但不包括仪器化冲击试验方法，这部分内容参见GB／T 19748。 2 规范性引用文件 下列文件对于本文件的应用是必不可少的。凡是注日期的引用文件，仅注日期的版本适用于本文件。凡是不注日期的引用文件，其最新版本(包括所有的修改单)适用于本文件。 GB／T 2975 钢及钢产品 力学性能试验取样位置及试样制备(GB／T 2975—2018，ISO 377：2017，MOD) GB／T 3808 摆锤式冲击试验机的检验(GB／T 3808—2018，ISO 148-2：2008，MOD) GB／T 8170 数值修约规则与极限数值的表示和判定 JJG 145 摆锤式冲击试验机检定规程 3 术语和定义 下列术语和定义适用于本文件。 3．1 能量相关定义 3．1．1 初始势能 initial potential energy 势能 potential energy Kp 在落摆进行冲击试验前摆锤的势能，由直接校准确定。 3．1．2 吸收能量 absorbed energy K 采用摆锤冲击试验机使试样发生断裂需要的能量，该能量是进行摩擦修正后的值。 注：用字母V或U表示缺口几何形状，用字母W代表无缺口试样，用下标数字2或8表示摆锤锤刃半径，例如KV2。 3．1．3 初始势能标称值 nominal initial potential energy 能量标称值 nominal energy KN 由冲击试验机制造商给定的名义能量值。 3．2 试样相关定义 3．2．1 宽度 width W 开缺口面与其相对面之间的距离。 注1：对于无缺口试样为打击中心所在面与其相对面之间的距离。 注2：见图1。 注3：在GB／T 229—2007中开缺口面与其相对面之间的距离定义为“高度”，替换为“宽度”是为了与其他原理相同的断裂标准保持一致。 3．2．2 厚度 thickness B 垂直于宽度方向且与缺口轴线平行的尺寸。 注1：对于无缺口试样为与宽度方向垂直的最小尺寸。 注2：见图1。 注3：在GB／T 229—2007中垂直于宽度方向且与缺口轴线平行的尺寸定义为“宽度”，替换为“厚度”是为了与其他原理相同的断裂标准保持一致。 3．2．3 长度 length L 与缺口方向垂直的最大尺寸。 注1：对于无缺口试样为与宽度方向垂直的最大尺寸。 注2：缺口方向即缺口深度方向，见图1。 说明： 1——砧座； 4——保护罩； 7——试样厚度，B； 2——标准尺寸试样； 5——试样宽度，W； 8——打击点； 3——试样支座； 6——试样长度，L； 9——摆锤冲击方向。 注：保护罩可用于U型摆锤试验机，用于保护断裂试样不回弹到摆锤和造成卡锤。 图1 试样与摆锤冲击试验机支座及砧座相对位置示意图 4 符号和说明 本文件使用符号和说明见表1。 表1 符号、名称及单位 符号 单位 名称 B mm 试样厚度 α ° 摆锤释放时的角度 β1 不安装试样时摆锤下落的升角 β2 不安装试样且不复位指针时摆锤下落的升角 L mm 试样长度 LE mm 侧膨胀值 K J 吸收能量(以KV2、KV8、KU2、KU8表示不同的缺口几何形状和不同锤刃半径) K1 J 不安装试样时摆锤下落的指示吸收能量 K2 J 不安装试样且不复位指针时摆锤下落的指示吸收能量 KN J 初始势能标称值 Kp J 初始势能(势能) KT J 总吸收能量 KV2 J V型缺口试样使用2 mm摆锤锤刃测得的冲击吸收能量 KV8 J V型缺口试样使用8 mm摆锤锤刃测得的冲击吸收能量 KU2 J U型缺口试样使用2 mm摆锤锤刃测得的冲击吸收能量 KU8 J U型缺口试样使用8 mm摆锤锤刃测得的冲击吸收能量 KW2 J 无缺口试样使用2 mm摆锤锤刃测得的冲击吸收能量 KW8 J 无缺口试样使用8 mm摆锤锤刃测得的冲击吸收能量 M N·m 摆锤力矩，等于F·l2 ρ J 由指针摩擦带来的能量损耗 ρ′ J 由轴承摩擦和空气阻力带来的能量损耗 ρβ J 仰角β对应的修正能量损耗 SFA ％ 剪切断面率 Tt ℃ 转变温度 W mm 试样宽度 Tt27 ℃ 由指定吸收能量值(例如27 J)确定的转变温度 Tt50％US ℃ 由指定吸收能量上平台的百分数(例如50％)确定的转变温度 Tt50％SFA ℃ 由指定剪切断面率(例如50％)确定的转变温度 Tt0.9 ℃ 由指定侧膨胀值(例如0.9 mm)确定的转变温度 5 试验原理 本标准规定的试验采用摆锤单次冲击的方式使试样破断，试验条件由第6章、第7章和第8章给出。试样的缺口有规定的几何形状并位于两支座的中心、打击中心的对面。测定参数包括吸收能量、侧膨胀值和剪切断面率等。由于很多材料的冲击结果会随温度变化而变化，试验应在给定温度条件下进行，当给定温度不是室温时，试样应在可控温度下进行加热或冷却。 注1：夏比摆锤冲击试验是工业应用方面常用的验收判定试验，对于这类试验，试样完全断裂、部分断裂或者只是发生塑性变形并划过砧座，这些情况并不重要。在理论研究方面，需对测定的能量值进行深入研究，测定的能量值可能与试样是否破断有很大关系。 注2：需要注意不是所有的夏比冲击试验结果都可以直接进行比较。例如，试验采用的摆锤锤刃半径可能不同，或采用不同形状的试样。采用不同摆锤锤刃可能导致试验结果产生差异[2]。这也是完整的试验报告除了执行标准还需包括明确的试验机类型、试样类型、试验后试样断裂情况等用于决定试验结果可比较性项目的原因。 6 试样 6．1 一般要求 6．1．1 标准尺寸冲击试样长度为55 mm，横截面为10 mm×10 mm方形截面。在试样长度的中间位置有V型或U型缺口，见6．2．1和6．2．2。 6．1．2 如试料不够制备标准尺寸试样，如无特殊规定，可使用厚度为7.5 mm、5 mm或2.5 mm的小尺寸试样(见图2和表2)，通过协议也可使用其他厚度的试样。 注1：只有采用形状和尺寸均相同的试样才可以对结果进行直接比较。 注2：对于低能量的冲击试验，用垫片使小尺寸试样位于摆锤中心位置以避免额外的能量吸收非常重要。对于高能量的冲击试验采用垫片的重要性会有所降低。垫片可以置于支座上方或者下方，使试样厚度的中心位置位于10 mm支座以上5 mm的位置(即标准试样的打击中心位置)。 6．1．3 对于需要进行热处理的试验材料，应在最终热处理后的试料上进行精加工和开缺口，除非可以证明在热处理前加工试样不会影响试验结果。 6．2 缺口几何形状 6．2．1 应仔细制备试样缺口，以保证缺口根部半径没有影响吸收能量的加工痕迹。缺口对称面应垂直于试样纵向轴线(见图2)。 6．2．2 V型缺口夹角应为45°，根部半径为0.25 mm[见图2a)和表2]，韧带宽度为8 mm(缺口深度为2 mm)。 6．2．3 U型缺口根部半径为1 mm[见图2b)和表2]，韧带宽度为8 mm或5 mm(缺口深度为2 mm或5 mm，除非另有规定)。 6．3 试样尺寸的偏差 指定试样和缺口的尺寸偏差见图2和表2。 a) V型缺口 b) U型缺口 注：符号L、W、B和数字1～5的尺寸见表2。 图2 夏比摆锤冲击试样 表2 试样的尺寸与偏差 名称 符号或 序号 V型缺口试样a U型缺口试样 名义尺寸 机加工公差 名义尺寸 机加工公差 试样长度 L 55 mm ±0.60 mm 55 mm ±0.60 mm 试样宽度 W 10 mm ±0.075 mm 10 mm ±0.11 mm 试样厚度标准尺寸试样 10 mm ±0.11 mm 10 mm ±0.11 mm 试样厚度小尺寸试样b B 7.5 mm ±0.11 mm 7.5 mm ±0.11 mm 5 mm ±0.06 mm 5 mm ±0.06 mm 2.5 mm ±0.05 mm — — 缺口角度 1 45° ±2° — — 韧带宽度 2 8 mm ±0.075 mm 8 mm ±0.09 mm — — 5 mm ±0.09 mm 缺口根部半径 3 0.25 mm ±0.025 mm 1 mm ±0.07 mm 缺口对称面端部距离 4 27.5 mm ±0.42 mmc 27.5 mm ±0.42 mmc 缺口对称面试样纵轴角度 90° ±2° 90° ±2° 试样相邻纵向面间夹角 5 90° ±1° 90° ±1° 表面粗糙度d Ra ＜5 μm — ＜5 μm — a 对于无缺口试样，要求与V型缺口试样相同(缺口要求除外)。 b 如指定其他厚度(如2 mm或3 mm)，应规定相应的公差。 c 对端部对中自动定位试样的试验机，建议偏差采用±0.165 mm代替±0.42 mm。 d 试样的表面粗糙度Ra应优于5 μm，端部除外。 6．4 试样的制备 试样样坯的切取应按相关产品标准或GB／T 2975的规定执行，试样制备过程应使任何可能令材料发生改变(例如加热或冷作硬化)的影响减至最小。 6．5 试样的标记 试样标记可以标在不与支座、砧座及摆锤锤刃接触的试样表面上。由试样标记导致的塑性变形和表面不连续性不应对吸收能量产生影响(见8．8)。 7 试验设备 7．1 一般要求 所有测量仪器均应溯源至国家或国际基准。测量仪器应在合适的周期内进行校准。 7．2 安装及校准 试验机应按照GB／T 3808或JJG 145的要求进行安装及校准。 7．3 摆锤锤刃 摆锤锤刃边缘曲率半径应为2 mm或8 mm两者之一。用符号的下标数字表示：KV2、KV8、KU2、KU8、KW2、KW8。摆锤锤刃半径的选择应依据相关产品标准的规定。 注：采用2 mm和8 mm摆锤锤刃得到的试验结果可能有差异。 8 试验程序 8．1 一般要求 8．1．1 试样应紧贴试验机砧座，试样缺口对称面与两砧座中间平面间的距离应不大于0.5 mm。锤刃打击中心位于缺口对称面、试样缺口的对面(见图1)，对于无缺口试样应使锤刃打击中心位于试样长度方向和厚度方向的中间位置。 8．1．2 试验前应检查砧座跨距，砧座跨距应保证在40＋0.20 mm以内；并检查砧座网角和摆锤锤刃部位是否有损伤或外来金属粘连，如发现存在问题应对问题部件及时调整、修磨或更换以保证试验结果的准确可靠。 8．2 摩擦损耗的测定 8．2．1 每天开始进行冲击试验前应对摩擦造成的能量损耗进行检查。可以按下述方法进行摩擦损耗的评估，也可采用其他方法。 注：摩擦的能量损耗包括但不限于空气阻力、轴承摩擦和指针摩擦。试验机摩擦的增加会影响吸收能量的测量。