晶体的范性形变是由大量位错集体运动造成的。弥散沉淀粒子或弥散气泡引起金属力学强度显著变化又反映了这些弥散粒子或弥散气泡与位错交互作用的事实。解释掺Si、Al、K的钨丝具有良好的抗下垂性能的“钾泡弥散强化说”就是弥散强化理论应用的一个典型例子。关于这方面的研究,以往进行了大量的工作,但有些问题还不太清楚,或缺少直接的实验证明。例如位错与钾泡的交互作用过程以及钾泡在裂纹成核和掺杂钨丝断裂中的作用等等。我们在高压电镜中对掺杂钨丝的形变和断裂进行的原位观察,在这方面提供了一些直接的例证。我们的观察也发现螺型位错是很直的,其运动特点是间断式的,这和Tabata等在纯钨单晶中观察到的特点一致。但在我们的实验中,位错运动明显地受到钾泡列的阻碍作用。图1是一组从磁带录象上复制的照片,在晶界附近的位错源已开动,不断发射出位错,但就在其近旁的位错,由于受到钾泡的钉扎作用,并未运动。迹线分析表明该晶粒的膜面为(221),两组螺型位错与钾泡列[110]方向成27.5°角。其Burgers矢量分别为a/2[111]和a/2 The normal deformation of the crystal is caused by the collective movement of a large number of dislocations. Diffusion of precipitated particles or diffusive bubbles causes a significant change in the mechanical strength of the metal and reflects the fact that these diffusive particles or diffusive bubbles interact with dislocations. Explain the “Si-Al, K-doped tungsten wire with good anti-sagging performance of the” potassium bubble dispersion strengthening that "is a typical application of dispersion strengthening theory. A great deal of work has been done on this aspect of research, but some questions are still unclear or there is a lack of direct experimental evidence. Such as the interaction between dislocations and potassium bubbles and the role of potassium bubbles in nucleation and doping of tungsten. Our in-situ observations of the deformation and fracture of the doped tungsten wire in high-pressure electron microscopy provide some direct examples in this regard. Our observations also show that screw dislocations are straight and their motional characteristics are discontinuous, consistent with what Tabata et al. Observed in pure tungsten single crystals. However, in our experiments, the dislocation movement was apparently hindered by the potassium bubble column. Figure 1 shows a set of photographs taken from a videotape recording where dislocation sources near the grain boundaries have been activated and emit dislocations continuously but dislocations in the immediate vicinity of them are pinned by potassium bubbles and Not exercise. Trace analysis shows that the membrane surface is (221) and the two sets of screw dislocations form an angle of 27.5 ° with the direction of the potassium bubble [110]. The Burgers vectors are a / 2 [111] and a / 2, respectively