The Future of Thermally Processing Titanium In A Vacuum Furnace Robert Hill Jr. Solar Atmospheres of Western PA USA

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1 The Future of Thermally Processing Titanium In A Vacuum Furnace Robert Hill Jr. Solar Atmospheres of Western PA USA Abstract: Discussion will begin with the importance of the vacuum furnace while developing titanium on a production basis in the 1950 s. The current state of vacuum technology will ensue. Numerous real life examples of commercially vacuum processed parts will be presented. The talk will concluded with a discussion on the dire need of revision and updated old antiquated titanium specifications. 1.0 Introduction: The Latin word vacuum meaning emptiness is void of air whereas that gas density may vary over 19 orders of magnitude. Many precautions must be heeded whenever one thermally processes titanium. These dangers primarily exist due to the fact that titanium is not found in its natural state. Therefore, element #22 is very reactive with many other elements in particular oxygen and hydrogen. These specific elements are very detrimental to the ultimate desired properties, especially within aerospace applications. The importance of minimizing and eliminating alpha case and hydrogen embrittlement is a direct result of the vacuum furnace. 2.0 Current State of Vacuum Processing: The vacuum furnace has evolved over many years. Today we are experiencing deeper vacuum levels, tighter pyrometry controls, and purer and drier inert processing gases. Solar s new patented dual car bottom loading vehicle (US Patent 6,936,792 B2 on August 30, 2005) has enabled Solar to process some of the most difficult and challenging projects. This innovative loading mechanism also enables Solar to process as much as 150,000 pounds at one time! 3.0 Titanium Vacuum Processing: Numerous real life examples of typical vacuum thermally processed parts will be presented. The markets represented are from the aerospace, medical, power generation, and commercial arenas. The thermal processes of these various markets include vacuum degassing, vacuum annealing, vacuum stress relieving, vacuum homogenization, vacuum solution treating and aging, and vacuum creep forming. 4.0 The Future of Titanium Vacuum Processing: Newer alloys are being developed to promote the need for nearer net shapes of titanium components. Their corresponding titanium specifications, along with more

2 mature specifications, must be revised to include better directives especially on the quench methods. These improvements will enhance the repeatability and overall quality of thermally processed titanium components. 5.0 Conclusion: Titanium is a very difficult member of the metallurgical family. Being a very reactive element, the vacuum furnace was the answer to many inherent problems of this metal in the past. In the future, it is this author s opinion, that vacuum processing will be as important as newer titanium alloys are designed and their specifications are revised. Contact: Robert Hill Jr. 30 Industrial Road Hermitage. PA (w) (c) rah@solaratm.com Webpage:

3 The Future of Thermally Processing Titanium In A Vacuum Furnace Robert Hill Jr. President Solar Atmospheres of Western PA USA International Titanium Association Annual Conference Heat Treating / Testing Panel September 15 th, 2009

4 Vacuum, - What is it? Vacuum is simply the opposite of pressure. Vacuum is a region in space in which the pressure is less than atmospheric pressure. Vacuum pressures range over 19 orders of magnitude.

5 We Use Vacuum To Avoid Air

6 We Use Vacuum To Avoid Air To Prevent Alpha Case

7 We Use Vacuum To Reduce Hydrogen Levels To Prevent Hydrogen Embrittlement

8 The Answer? The Vacuum Furnace 1954

9 Today s s Vacuum Furnace Attains Vacuum Levels 1x10-5 Torr or Lower

10 Today s s Vacuum Furnace Possess High Temperature Capabilities

11 Today s s Vacuum Furnace Possess Uniform Pyrometry Controls

12 Today s s Processing Gases Must Be Dry & Pure Dewpoint in F Nitrogen Dewpoint in F Helium Dewpoint in F Argon Dewpoint in F Hydrogen /19/2009 Dew Point Chart 2009

13 Solar s s Patented Dual Car Bottom Load Car Design Increased Production, The ability to load extreme weight 150,000 Lbs

14 Dual Car Bottom Load Cars Provides a flat stable work hearth to within over 36 length

15 Vacuum Annealing

16 Vacuum Degassing

17 Vacuum Stress Relief

18 Vacuum Homogenizing

19 Titanium / Stainless (Nickel) Eutectic = 1769 F

20 Vacuum Creep Forming

21 The Future of Vacuum Processing Titanium Thermal Processing which enhances near net shapes

22 BAC 5613 Approved Sources

23 The Future of Vacuum Processing Titanium Revising Antiquated Specification, AMS 2801 (Aerospace Specification for Titanium Parts

24 The Future of Vacuum Processing Titanium Inert High Pressure Gas Quenching

25 The Future of Vacuum Processing Titanium Inert High Pressure Gas Quenching

26 The Future of Vacuum Processing Titanium

27 The Future of Vacuum Processing Titanium Titanium Metallurgists must interact with SAE / AMEC committees to revise and update AMS heat treat specifications

28 Thank You