Bapna M S, Lautenschlager E P, Moser J B
J Biomed Mater Res. 1975 Nov;9(6):611-21. doi: 10.1002/jbm.820090607.
The influence of both imposed anodic potential in Ringer's solution and surface finish on the fatigue lives of annealed 316 type stainless steel and annealed pure titanium were measured and statistically compared to fatigue data run in air. The applied potentials in simulated extracellular fluid approximated conditions existing within the body while also producing the types of surface defects actually found on removed long time implants within the time interval of the accelerated R. R. Moor fatigue tests. Differentiating tests were run at single levels of applied cyclic stress well above the endurance limits. In Ringer's solution, the fatigue life of the 316 stainless steel decreased with increasing applied potential, and at +500 mV was significantly shorter than when run in air. At each condition, the 316 stainless steel was independent of initial surface finish. In contrast, the fatigue life of titanium improved rapidly with increasingly fine surface finishes. Furthermore, compared to air, the application of +500 mV in Ringer's solution improved the life of the rough surface finished material and markedly increased to number of cycles to failure for the electopolished specimens.
在林格氏溶液中施加阳极电位以及表面光洁度对退火态316型不锈钢和退火态纯钛疲劳寿命的影响进行了测量，并与在空气中运行的疲劳数据进行了统计比较。模拟细胞外液中的施加电位近似于体内存在的条件，同时在加速的RR摩尔疲劳试验的时间间隔内，也会产生在取出的长期植入物上实际发现的表面缺陷类型。区分试验在远高于耐力极限的单级施加循环应力下进行。在林格氏溶液中，316不锈钢的疲劳寿命随着施加电位的增加而降低，在+500 mV时明显短于在空气中运行时的寿命。在每种条件下，316不锈钢与初始表面光洁度无关。相比之下，钛的疲劳寿命随着表面光洁度越来越细而迅速提高。此外，与空气相比，在林格氏溶液中施加+500 mV可提高粗表面光洁度材料的寿命，并显著增加电解抛光试样的失效循环次数。
