Large thermal hysteresis NiTi Belleville washer fabricated by metal injection moulding

ABSTRACT

In this work, Ni_49.4Ti_50.6 Belleville washers are prepared by metal injection moulding (MIM). The martensitic transition temperatures and service performance of washers were investigated. The thermal hysteresis has reached 63.1–71.6°C, which is much higher than documented data in binary NiTi alloys. Ti₂Ni and Ni₄Ti₃ phase are observed in XRD patterns, which is responsible for the large thermal hysteresis. In the service tests, the restoring forces are higher than 40 kN, which are sufficient to ensure a tight connection of the fasteners. The loop resistance and high-current test have proved the safety of MIM NiTi Belleville washers compared to traditional steel spring washers, which can meet the challenge in complex outdoor circumstances.

KEYWORDS:

• Belleville washer
• metal injection moulding
• NiTi alloy
• fastener
• large thermal hysteresis

Acknowledgements

The authors acknowledge support from the National Natural Science Foundation of China (grant number 51804271), Guangxi Natural Science Foundation (2018GXNSFAA28123 7), Guangxi Liuzhou LiuDong Science Technology Project(2018000005).

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

The authors acknowledge support from the National Natural Science Foundation of China [grant number 51804271], Guangxi Natural Science Foundation [grant number 2018GXNSFAA281237], Guangxi Liuzhou Liudong Science Technology Project [grant number 2018000005].