- 學位論文
雷射處理對生醫不銹鋼之表面結構與特性影響
Laser processing and its effects on surface structure and properties of biomedical stainless steels
摘要
本研究基於表面改質之基礎概念，藉由光學顯微鏡、掃描式電子顯微鏡、穿透式電子顯微鏡和X射線繞射研究經表面雷射處理後之304不銹鋼，其表面顯微結構與特性。試片經雷射處理後，合金表面會生成一伴隨著多孔性結構之重鑄層。此重鑄層之厚度約為0.5 至 1 μm，而表面粗糙度接近於60 至 160 nm。此外，細胞毒性之MTT檢測係根據ISO 10993標準測試，且纖維母細胞NIH3T3亦會被培養於未處理之不銹鋼與雷射處理過後之不銹鋼上觀察其生長情形。細胞實驗研究結果顯示；纖維母細胞於雷射處理過後之304不銹鋼表面生長情形會較未處理不銹鋼好。細胞毒性之MTT檢測亦指示；雷射處理過後之不銹鋼不會釋出毒性金屬離子至細胞中。因此，重鑄層可被相信是扮演一重要角色於增加合金之生物相容性上。這些研究結果特徵有助於近一步了解雷射表面處理對不銹鋼表面之生物相容性與顯微結構之間關係；用於發展成一新型具有良好生物相容性之醫用植體合金。
並列摘要
The study is based on the concept of surface modification to investigate the surface microstructure and properties of the 304 stainless steel (SS) substrate after laser treatment by means of optical microscope, scanning electron microscope, transmission electron microscope and X-ray diffraction. After laser treatment of the specimen, the surface of the alloy will produce a recast layer with porous structure. Its thickness is about 0.5 to 1 μm, and roughness is approximately 60 to 160 nm. Furthermore, the MTT assay was performed according to ISO 10993 specifications and observed the situation of fibroblasts (NIH3T3) growth on the surfaces of treated and without treated AISI 304 SS. The results showed that as the AISI 304 SS with laser treatment, the attached situation of fibroblasts is better to than that of untreated sample. The MTT assay results also indicated that treated AISI 304 SS was not released toxic metallic ions to cells. It is believed that the recast layer played an important role to enhance the biocompatibility of the alloy. These features can be useful in further understanding the relationship between the microstructure and biocompatibility of the laser treatment on alloy surface, to development as a new medical implant alloy with good biocompatibility.