Swelling of SiC at 300${}^{\circ }$C due to in-service neutron irradiation causes tensile residual stresses in coatings which are expected to adversely affect the performance of coated SiC composite fuel cladding for light water reactors. Matching the coating swelling with the substrate, a solution common for thermal expansion, is not practical in the case of neutron irradiation. Biasing samples during magnetron sputtering deposition induces compressive residual stress which may counteract this. In this study, chromium coatings were deposited on SiC by DC magnetron sputtering with no external heating at bias voltages of -50V, -75V, and -100V. The effects of the bias voltage on morphology, residual stress, microstrain, texture, and adhesion are shown. The low deposition temperature resulted in the coating microstructure evolution following an energetic particle bombardment dominated trend. At the two lower bias voltages knock-on implantation dominated increasing the residual stress and microstrain while at the highest bias voltage, thermal spike migration allowed for defect relaxation. When the knock-on induced compressive residual stress exceeded 0.8 GPa microcrack formation in the SiC substrate decreased coating adhesion. While no microcracks formed at the lowest bias voltage, insufficient atomic mobility during coating growth lead to voids forming in the coating. A balance is needed to form void-free coatings that have high compressive residual stress.

碳化硅在 300 时的溶胀${}^{\circ }$由于在役中子辐照，C 导致涂层中的拉伸残余应力，这预计会对轻水反应堆涂层 SiC 复合燃料包壳的性能产生不利影响。使涂层溶胀与基材相匹配，这是一种常见的热膨胀解决方案，在中子辐射的情况下是不切实际的。在磁控溅射沉积过程中偏置样品会引起压缩残余应力，这可能会抵消这一点。在这项研究中，在 -50V、-75V 和 -100V 的偏置电压下，通过直流磁控溅射在 SiC 上沉积铬涂层，无需外部加热。显示了偏压对形态、残余应力、微应变、质地和粘附力的影响。低沉积温度导致涂层微观结构演变遵循高能粒子轰击主导的趋势。在两个较低偏压下，敲击式注入主要增加残余应力和微应变，而在最高偏压下，热尖峰迁移允许缺陷松弛。当撞击引起的残余压缩应力超过 0.8 GPa 时，在 SiC 衬底中形成的微裂纹会降低涂层的附着力。虽然在最低偏置电压下没有形成微裂纹，但涂层生长过程中原子迁移率不足会导致涂层中形成空隙。需要平衡以形成具有高压缩残余应力的无空隙涂层。在两个较低偏压下，敲击式注入主要增加残余应力和微应变，而在最高偏压下，热尖峰迁移允许缺陷松弛。当撞击引起的残余压缩应力超过 0.8 GPa 时，在 SiC 衬底中形成的微裂纹会降低涂层的附着力。虽然在最低偏置电压下没有形成微裂纹，但涂层生长过程中原子迁移率不足会导致涂层中形成空隙。需要平衡以形成具有高压缩残余应力的无空隙涂层。在两个较低的偏压下，敲击式注入主要增加残余应力和微应变，而在最高偏压下，热尖峰迁移允许缺陷松弛。当撞击引起的残余压缩应力超过 0.8 GPa 时，在 SiC 衬底中形成的微裂纹会降低涂层的附着力。虽然在最低偏置电压下没有形成微裂纹，但涂层生长过程中原子迁移率不足会导致涂层中形成空隙。需要平衡以形成具有高压缩残余应力的无空隙涂层。涂层生长过程中原子迁移率不足导致涂层中形成空隙。需要平衡以形成具有高压缩残余应力的无空隙涂层。涂层生长过程中原子迁移率不足导致涂层中形成空隙。需要平衡以形成具有高压缩残余应力的无空隙涂层。