DENTAL CASTING OF TITANIUM ALLOYS

失蜡铸造技术在牙科铸造中占据主导地位 制作牙冠和桥的方法已有多年。然而，由于 20世纪70年代末，S努力做到了案件的固定和拆卸 使用商业纯(CP)钛的牙科修复体，它具有 机械性能类似于ADA I-IV类金合金。这个 与其他金属相比，钛的压倒性优势是它的卓越 生物兼容性，这一点很重要，因为人们越来越担心 生物医学材料的毒性。此外，钛是一种 经济型金属(30美元/盎司，贵重合金350美元/盎司) 供应充足。牙科钛铸造最初的许多问题 由于钛的固有特性而产生的问题现在已经得到解决。 目前有各种商业铸造设备和 可获得专门为牙科开发的投资材料 钛铸件。然而，钛铸件的进一步细化 技术仍有待改进，特别是铸造合金方面。主 这项计划的目标是开发低熔点的钛合金。 温度和高抗氧化性，这将导致铸造 性能、机械和腐蚀性能、生物兼容性以及 可加工性与CP钛和ADA IV型金合金相同或更好。 具体地说，拟议的项目将首先尝试找到合适的 CP用NIOM/贝勒铸钛设备的浇注条件 钛和钛-6Al-4V。在铸造工艺用这个精炼之后 设备，二元候选合金将根据机械设备进行筛选 性能和耐腐蚀性。实验二进制和三进制 合金(基于筛选的二进制)将根据以下条件进行评估 铸造性能，机械性能，腐蚀行为， 微观结构和生物相容性。材料可加工性的研究进展 选定的实验合金将尝试通过合金化小 为改善此属性而注明的元素数量。最后，自然界 将在选定的试验性钛上评估烤瓷粘结的性能 合金。本研究小组认为，拟议的研究是一项 推进这一“技术敏感”进程的重要一步 一个更实际的层次。钛在牙科中有很大的潜力 挑选申请者，而忽视它，将是对公众的伤害。 然而，为了让公众受益，需要在以下方面做更多的工作 完善钛铸件工艺的各个方面。这是 这项提案所涉及的工作。

Dental casting by means of the lost-wax technique has been the dominant method of fabricating crowns and bridges for many years. However, since the end of the 1970's, efforts have been made to case fixed and removable dental prostheses using commercially pure (CP) titanium, which has mechanical properties similar to ADA Types I-IV gold alloys. The overwhelming advantage of titanium over other metals is its excellent biocompatibility, which is important because of increasing concerns about the toxicity of biomedical materials. In addition, titanium is an economical metal ($30/oz vs. $350/oz for a precious alloy) and is in abundant supply. Many of the initial problems with dental titanium casting arising from the inherent characteristics of titanium have now been solved. There are presently various kinds of commercial casting equipment and investment materials available which were specifically developed for dental titanium casting. However, further refinement of titanium casting technology remains to be done, particularly the casting alloys. The main goal of this proposal is to develop titanium alloys which have a low fusing temperature and high oxidation resistance which will result in casting performance, mechanical and corrosion properties , biocompatibility, and machinability equal or superior to CP titanium and ADA Type IV gold alloy. Specifically, the proposed project will attempt first to find suitable casting conditions for the NIOM/Baylor titanium casting equipment for CP titanium and Ti-6AI-4V. After the casting technology is refined with this equipment, binary candidate alloys will be screened based on mechanical properties and corrosion resistance. Experimental binary and ternary alloys (based on the screened binaries) will be evaluated in terms of casting performance, mechanical properties, corrosion behavior, microstructure, and biocompatibility. Advancements in the machinability of the selected experimental alloys will be attempted by alloying small amounts of elements noted for improving this property. Finally, the nature of porcelain bonding will be evaluated on selected experimental titanium alloys. The present research group believes the proposed study to be an important step for the advancement of this "technique-sensitive" process to a more practical level. There is great potential for titanium in dental casting applications and to ignore it would be a disservice to the public. In order for th e public to benefit, however, more work needs to be done on perfecting all aspects of the titanium casting technology. This is the work that this proposal addresses.