以氦气作为冷媒, 利用G-M制冷机作为冷源, 可实现室温至-269℃ (4.2K) 全范围内的低温环境.将其与常规材料拉伸试验机相结合, 建立了金属材料深冷低温拉伸测试系统.解决好深冷环境下试验系统的密封与漏热问题, 是实现低温拉伸测试的关键技术环节.在-196℃ (77K) 以上温度区间, 采用液氮辅助预冷的方法, 可显著提高系统的降温速率, 相比于常规直接以液氮或液氦为冷源的制冷方式, 利用制冷机制冷进行低温拉伸测试的方法, 不仅适用温度范围广, 且可极大地降低试验成本, 兼具实用性与经济性.%A testing system was developed for tensile test of metallic materials in the whole range from ambient temperature to-269℃ (4. 2 K). The low temperature environment was created with G-M refrigerator as cooling source and gas helium as coolant. The key to realize cryogenic temperature environment was good system sealing and reducing the heat loss to the surroundings. In the temperature range above-196℃ (77 K), the system cooling rate can be significantly accelerated by pre-cooling with liquid nitrogen. Creating low temperature environment with G-M refrigerator is more practical and economical than the conventional refrigeration ways, such as using liquid nitrogen or helium as the cold source. It gets broad test temperature range, but needs less liquid helium, which is rare and expensive.
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