直流电热处理对镍钛合金丝三点弯曲性能的影响  

Properties of NiTi wires with direct electric resistance heat treatment method in three-point bending tests

作　　者：王红梅[1] 王邦康[1] 任超超[1] 白玉兴[1] 

机构地区：[1]首都医科大学口腔医学院正畸科,北京100050

出　　处：《中华口腔医学杂志》2011年第3期168-171,共4页Chinese Journal of Stomatology

基　　金：首都医学发展科研基金（2005-2018）

摘　　要：目的 探讨直流电热处理后镍钛合金丝三点弯曲性能的变化规律,以期更好地发挥镍钛合金丝在临床治疗中的作用.方法 选择两种超弹性镍钛合金丝（弓丝A：圣马特超弹性镍钛合金牙齿矫形丝;弓丝B：SENTALLOY（R）超弹性镍钛合金丝）和两种热激活镍钛合金丝（弓丝C：圣马特热激活镍钛合金牙齿矫形丝;弓丝D：L＆H镍钛丝）,用加热仪分别对弓丝进行0（对照）、1.0、1.5、2.0、2.5 s的直流电热处理（恒定电流强度6.36 A）;在37℃下利用三点弯曲实验检测弓丝的性能变化.结果 热处理后镍钛合金丝的平台期应力值均有所增加,加热2.0 s后弓丝A、B、C、D中点加载位移1.5 mm时,应力值分别为（4.33±0.07）、（4.52±0.08）、（4.07±0.05）、（3.27±0.15）N,与对照[分别为（3.85±0.11）、（3.28±0.09）、（3.62±0.07）、（2.91±0.23）N]相比,差异有统计学意义（P＜0.05）.结论 在正畸治疗的不同阶段可利用直流电热处理的方法改变镍钛合金丝的形状和超弹性,但应注意控制加热的电流强度和时间,随着加热时间的延长,弓丝硬度增加.Objective To investigate the mechanical properties of Ni-Ti wires with direct electric resistance heat treatment（DERHT） method in three-point bending tests. Methods Two superelastic Ni-Ti wires（wire A： Smart SE, wire B： SENTALLOY SE, 0.406 mm ×0.559 mm） and 2 heat-actived Ni-Ti wires（wire C： Smart SM, wire D： L＆H TITAN, 0.406 mm ×0.559 mm） were selected. They were heattreated using the DERHT method by a controlled electric current（6. 36 A） applied for different period of time[0（control）, 1.0, 1.5, 2. 0, 2. 5 seconds）. Then, a three-point bending test was performed under controlled temperature （37 ℃ ） to examine the relationships between the deflection and the load in the bending of wires. Results After DERHT treatment, the plateau in the force-deflection curve of superelastic Ni-Ti wires and heat-actived Ni-Ti wires were increased. When the wires were heated for 2. 0 seconds and deflected to 1.5 mm, the loading force of A, B, C and D Ni-Ti wires increased from （3.85 ± 0. 11 ）,（3.62±0.07）, （3.28±0.09）, （2.91 ±0.23） Nto （4.33 ±0.07）, （4.07 ±0.05）, （4.52±0.08）,（3.27 ± 0. 15 ） N respectively. Conclusions DERHT method is very convenient for clinical use. It is possible to change the arch form and superelastic force of NiTi wires. The longer the heating time is, the more the superelastic characteristics of the wires are altered.

关 键 词：正畸金属丝 三点弯曲实验 直流电热处理 

分 类 号：R783.5[医药卫生—口腔医学]