金属材料.摆锤式冲击试验.第2部分:测试机的鉴定

[中文适用范围]： ISO 148 的这一部分涵盖了摆锤式冲击试验机的结构元件、整体性能和结果准确性的验证。 它适用于具有 2 毫米或 8 毫米撞针的机器，用于进行摆锤冲击测试，例如根据 ISO 148-1。 可适用于各种容量、不同设计的摆锤冲击试验机。 根据 ISO 148 这一部分用于金属材料的工业、一般或研究实验室测试的冲击机被称为工业机器。 那些具有更严格要求的机器被称为参考机器。 参考机器验证的规范可在 ISO 148-3 中找到。 ISO 148 的这一部分描述了两种验证方法。 a) 直接法本质上是静态的，涉及对机器的关键部件进行测量，以确保其满足 ISO 148 本部分的要求。 用于验证和校准的仪器可追溯至国家或国际标准。 b) 间接法本质上是动态的，使用参考试件来验证测量标尺上的点的吸收能量。 参考试件的要求见摆锤冲击试验机在通过直接和间接方法验证并满足第 6 章和第 7 章的要求之前不符合 ISO 148 本部分。 本部分ISO 148 描述了如何评估试件断裂时吸收的总能量的不同组成部分。 该总吸收能量包括 - 使测试件本身断裂所需的能量，以及 - 摆锤冲击试验机从初始位置执行第一个半周期摆动的内部能量损失。 注：内部能量损失是由于以下原因造成的：空气阻力、旋转轴轴承和摆锤指示指针的摩擦力，可用直接法测定（见 6.4.5）；地基的冲击、框架和摆的振动，尚未开发出合适的测量方法和设备。 [外文原描述]： ISO 148-2:2016 covers the verification of pendulum-type impact testing machines, in terms of their constructional elements, their overall performance and the accuracy of the results they produce. It is applicable to machines with 2 mm or 8 mm strikers used for pendulum impact tests carried out, for instance, in accordance with ISO 148‑1. It can be applied to pendulum impact testing machines of various capacities and of different design. Impact machines used for industrial, general or research laboratory testing of metallic materials in accordance with this part of ISO 148 are referred to as industrial machines. Those with more stringent requirements are referred to as reference machines. Specifications for the verification of reference machines are found in ISO 148‑3. ISO 148-2:2016 describes two methods of verification. a) The direct method, which is static in nature, involves measurement of the critical parts of the machine to ensure that it meets the requirements of this part of ISO 148. Instruments used for the verification and calibration are traceable to national or international standards. b) The indirect method, which is dynamic in nature, uses reference test pieces to verify points on the measuring scale for absorbed energy. The requirements for the reference test pieces are found in ISO 148‑3. A pendulum impact testing machine is not in compliance with this part of ISO 148 until it has been verified by both the direct and indirect methods and meets the requirements of Clause 6 and Clause 7. ISO 148-2:2016 describes how to assess the different components of the total energy absorbed in fracturing a test piece. This total absorbed energy consists of - the energy needed to fracture the test piece itself, and - the internal energy losses of the pendulum impact testing machine performing the first half-cycle swing from the initial position. NOTE Internal energy losses are due to the following: - air resistance, friction of the bearings of the rotation axis and of the indicating pointer of the pendulum which can be determined by the direct method (see 6.4.5); - shock of the foundation, vibration of the frame and pendulum for which no suitable measuring methods and apparatus have been developed.