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

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 16148 (w) 1-888-982-0660 (c) 1-724-734-9303 Email: rah@solaratm.com Webpage: www.solaratm.com

The Future of Thermally The Future of Thermally

Processing Titanium In A Processing Titanium In A

Vacuum FurnaceVacuum Furnace

Robert Hill Jr. Robert Hill Jr.

PresidentPresident

Solar Atmospheres of Western PA USASolar Atmospheres of Western PA USA

International Titanium Association Annual ConferenceInternational Titanium Association Annual Conference

Heat Treating / Testing PanelHeat Treating / Testing Panel

September 15September 15thth, 2009, 2009

Vacuum, Vacuum, -- What is it?What is it?

Vacuum is simply the opposite of Vacuum is simply the opposite of pressure. pressure.

Vacuum is a region in space in which the Vacuum is a region in space in which the pressure is less than atmospheric pressure is less than atmospheric pressure. pressure.

Vacuum pressures range over 19 orders Vacuum pressures range over 19 orders of magnitude.of magnitude.

We Use Vacuum To Avoid AirWe Use Vacuum To Avoid Air

We Use Vacuum To Avoid Air To We Use Vacuum To Avoid Air To

PreventPrevent……

Alpha CaseAlpha Case

We Use Vacuum To Reduce We Use Vacuum To Reduce

Hydrogen Levels To Prevent Hydrogen Levels To Prevent ……

Hydrogen Hydrogen EmbrittlementEmbrittlement

The Answer? The Answer? The Vacuum FurnaceThe Vacuum Furnace

1954

Vacuum Levels 1x10 Torr or LowerVacuum Levels 1x10 Torr or Lower-5

TodayToday’’s Vacuum Furnace Attainss Vacuum Furnace Attains

High Temperature CapabilitiesHigh Temperature Capabilities

TodayToday’’s Vacuum Furnace Possess s Vacuum Furnace Possess

TodayToday’’s Vacuum Furnace Possess s Vacuum Furnace Possess

Uniform Uniform PyrometryPyrometry ControlsControls

TodayToday’’s Processing Gases Must s Processing Gases Must

Be Dry & PureBe Dry & Pure

3/19/2009 Dew Point Chart 2009

-120

-110

-100

-90

-80

-70

-60

-50

-40

Dewpoint in °F Nitrogen Dewpoint in °F Argon

Dewpoint in °F Helium Dewpoint in °F Hydrogen

SolarSolar’’s Patented Dual Car Bottom s Patented Dual Car Bottom

Load Car DesignLoad Car Design

Increased Production, The ability to load extreme weight – 150,000 Lbs

Dual Car Bottom Load CarsDual Car Bottom Load Cars

Provides a Provides a

flat stable flat stable

work hearth to work hearth to

within 0.015within 0.015””

over 36over 36’’ lengthlength

Vacuum AnnealingVacuum Annealing

VacuumVacuum

DegassingDegassing

VacuumVacuum

Stress Stress

ReliefRelief

Vacuum HomogenizingVacuum Homogenizing

Titanium / Stainless (Nickel) Titanium / Stainless (Nickel)

Eutectic = 1769Eutectic = 1769°°FF

Vacuum Creep FormingVacuum Creep Forming

The Future of Vacuum Processing The Future of Vacuum Processing

TitaniumTitaniumThermal Processing which enhances near Thermal Processing which enhances near

net shapesnet shapes

BAC 5613 Approved SourcesBAC 5613 Approved Sources

The Future of Vacuum Processing The Future of Vacuum Processing

TitaniumTitaniumRevising Antiquated Specification, AMS Revising Antiquated Specification, AMS

2801 (Aerospace Specification for 2801 (Aerospace Specification for

Titanium PartsTitanium Parts

The Future of Vacuum Processing The Future of Vacuum Processing

TitaniumTitanium

Inert High Pressure Gas Quenching

The Future of VacuumThe Future of Vacuum

Processing TitaniumProcessing Titanium

Inert High Pressure Gas Quenching

The Future of Vacuum The Future of Vacuum

Processing TitaniumProcessing Titanium

The Future of Vacuum The Future of Vacuum

Processing TitaniumProcessing Titanium

Titanium Metallurgists must interact with Titanium Metallurgists must interact with

SAE / AMEC committees to revise and SAE / AMEC committees to revise and

update AMS heat treat specificationsupdate AMS heat treat specifications

Thank YouThank You