Department of Removable Prosthodontics, Tsurumi University School of Dental Medicine, 2-1-3 Tsurumi, Tsurumi-ku, Yokohama, Japan.
Odontology. 2013 Jan;101(1):34-42. doi: 10.1007/s10266-011-0049-7. Epub 2011 Nov 12.
The purpose of the present study was to compare joint designs for the laser welding of cast metal plates and wrought wire, and to evaluate the welded area internally using X-ray micro-focus computerized tomography (micro-CT). Cast metal plates (Ti, Co-Cr) and wrought wires (Ti, Co-Cr) were welded using similar metals. The specimens were welded using four joint designs in which the wrought wires and the parent metals were welded directly (two designs) or the wrought wires were welded to the groove of the parent metal from one or both sides (n = 5). The porosity and gap in the welded area were evaluated by micro-CT, and the maximum tensile load of the welded specimens was measured with a universal testing machine. An element analysis was conducted using an electron probe X-ray microanalyzer. The statistical analysis of the results was performed using Bonferroni's multiple comparisons (α = 0.05). The results included that all the specimens fractured at the wrought wire when subjected to tensile testing, although there were specimens that exhibited gaps due to the joint design. The wrought wires were affected by laser irradiation and observed to melt together and onto the filler metal. Both Mo and Sn elements found in the wrought wire were detected in the filler metal of the Ti specimens, and Ni was detected in the filler metal of the Co-Cr specimens. The four joint designs simulating the designs used clinically were confirmed to have adequate joint strength provided by laser welding.
本研究的目的是比较用于铸造金属板和线材的激光焊接的接头设计，并使用 X 射线微焦点计算机断层扫描（micro-CT）对内焊接区域进行评估。使用类似的金属对铸造金属板（Ti、Co-Cr）和线材（Ti、Co-Cr）进行焊接。使用四种接头设计对样品进行焊接，其中线材和母材直接焊接（两种设计）或线材从一侧或两侧焊接到母材的凹槽中（n=5）。通过 micro-CT 评估焊接区域的孔隙率和间隙，并使用万能试验机测量焊接样品的最大拉伸载荷。使用电子探针 X 射线微分析仪进行元素分析。使用 Bonferroni 多重比较（α=0.05）对结果进行统计分析。结果包括，尽管由于接头设计，一些样品存在间隙，但所有样品在拉伸测试时均在线材处断裂。线材受到激光辐射的影响，观察到线材熔化并与填充金属结合在一起。在 Ti 样品的填充金属中检测到线材中的 Mo 和 Sn 元素，在 Co-Cr 样品的填充金属中检测到 Ni 元素。模拟临床上使用的设计的四种接头设计被证实具有足够的激光焊接接头强度。
