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RTI Proprietary Information

Reducing Titanium Cost

by Continuous Casting

K.O. Yu, M.P. Jacques and S.R. Giangiordano

RTI International Metals, Inc.

Titanium 2011

International Titanium Association Annual Meeting

October 2-5, 2011, San Diego, CA

Titanium 2011 October 2-5, 2011

RTI Proprietary Information 2

Introduction

• Existing Titanium Production Technology

* Batch type ingot making processes – VAR, PAM and EBM

* Large ingots need multiple hot working operations

* High energy consumption, yield loss, processing time

and production cost

• RTI Titanium Continuous Casting

* Based on mature PAM technology

* 5 patents, 2011 R&D 100 Award, 2010 NorTech Innovation Award

* Continuous process to make small diameter ingots

* Input stock for making castings, extrusions, bars and fasteners

* Lower energy consumption, yield loss, processing time and

production cost

• Status report for products made from round ingots


3

PAM (Plasma Arc Melting)

Process and Product

Copper

Crucible

Feeder

Pool Surface

Depression

Hearth

Solid

Skull

Continuously

Cast Ingot

Plasma Plume

Liquid

Pool Plasma Torch

13” x 34” x 80” Ti-64 Slab

15” Ø x 200” Lg Ti-64 Ingot

RTI Proprietary Information Titanium 2011 October 2-5, 2011


Schematic of PAM

Continuous Casting Process

Torch Temper-

ature

Sensor

Hearth

Glass

Container

Roller

Roller

Ingot

Ingot

Cutting

Torch

Casting

Mold

Heating

Coils

Ingot

Titanium ConCast

Process 20K lbs. 8-inch Ingots

Cast in One Campaign

RTI PAM H2

3-Torch

Furnace



8-inch Diameter Ingot

Exiting Furnace during

Campaign

Glass Coated 8.25”

Diameter Ingot

Guide Rollers

Furnace Chamber

5 Titanium 2011 October 2-5, 2011


Advantages of PAM ConCast

1. ConCast is a productivity enhancement from existing,

mature PAM technology

2. Flexible use of input materials

3. Ingots sized to reduce/eliminate hot working steps

4. Reduce processing time and improve productivity

5. Reduce delivery time and cost from conventional 2X

VAR processing route



Products made from

ConCast Ingots

Sponge PAM

Single

Melt

Scrap

Chips

Machining

Conditioning

Round

Billets

Slabs

Extruded Shapes/Tubes

Rolled Bars/Fasteners

Rolled Plates/Sheets

Investment Castings Casting

Electrodes

Rolled Rings


7


ConCast Ti-64 Alloy

Chemistry

8

Heat # &

Individual

ingot #

Trans. H2

ppm O2 % N % C % AI % V % Mo % Cr % Cu % Fe % Si % Sn % Mn %

Y

ppm

B

ppm Ni Zr

X10-5424-01

Edge

25

0.163 0.005 0.014 6.15 4.07 0.002 0.012 0.008 0.189 0.011 0.014 0.006 3 5 0.006 0.000

Mid-radius 0.168 0.006 0.013 6.04 4.03 0.001 0.011 0.014 0.187 0.011 0.01 0.005 2 4 0.006 0.000

Center 0.162 0.005 0.012 5.99 3.97 0.001 0.011 0.008 0.184 0.009 0.008 0.004 1 3 0.005 0.000

X10-5424-02

Edge

25

0.171 0.005 0.016 6.19 4.20 0.002 0.012 0.006 0.180 0.010 0.016 0.006 2 6 0.006 0.000

Mid-radius 0.176 0.006 0.016 6.16 4.03 0.001 0.012 0.006 0.186 0.010 0.012 0.005 2 5 0.006 0.000

Center 0.171 0.006 0.013 6.13 3.99 0.002 0.012 0.006 0.179 0.010 0.010 0.006 2 5 0.006 0.000

X10-5424-02

Edge

24

0.176 0.006 0.016 6.06 4.06 0.002 0.012 0.008 0.189 0.010 0.014 0.006 3 6 0.006 0.000

Mid-radius 0.177 0.005 0.014 6.01 3.99 0.001 0.012 0.006 0.185 0.010 0.012 0.006 2 5 0.006 0.000

Center 0.176 0.006 0.013 6.07 4.01 0.001 0.012 0.007 0.180 0.010 0.012 0.005 2 5 0.006 0.000

X10-5424-03

Edge

19

0.175 0.005 0.014 6.14 4.23 0.001 0.010 0.004 0.177 0.010 0.015 0.004 1 3 0.004 0.000

Mid-radius 0.170 0.005 0.015 6.22 4.27 0.001 0.011 0.004 0.185 0.010 0.017 0.005 1 3 0.005 0.000

Center 0.167 0.005 0.024 6.22 4.30 0.002 0.013 0.006 0.185 0.010 0.002 0.007 3 6 0.007 0.000

X10-5424-03

Edge

22

0.181 0.005 0.013 6.16 3.88 0.001 0.100 0.004 0.160 0.009 0.007 0.004 1 3 0.004 0.000

Mid-radius 0.177 0.006 0.02 6.18 3.96 0.001 0.100 0.004 0.160 0.009 0.009 0.004 1 3 0.004 0.000

Center 0.178 0.006 0.012 6.24 3.96 0.001 0.011 0.005 0.171 0.010 0.011 0.005 1 4 0.005 0.000

AMS 6945A ≤150 ≤0.20 ≤0.05 ≤0.08 5.5-6.75 3.5-4.50 ≤0.30 ≤50



2 x VAR ConCast Ingot

Sponge, Bulk Scrap Sponge, Small Scrap, Turnings

Make Compacts Make Compacts

Weld Electrode

1st VAR

2nd VAR PAM

1st Billet

2nd + Billet

3rd Billet

GFM Forging

Machining Machining

Final Billet Final Billet

Current production Continuous casting provides

process advantages to PAM

Long lead time Short lead time

Comparison of Processing Steps for Extrusion Billet Production Processes


Extrusions from Concast Billets

Extrusions made from

ConCast Billets

10

Titanium 2011 October 2-5, 2011 RTI Proprietary Information


Back End Macrostructure of X10-5422-07 T7

Extrusion Ratio: 33.8, 2190F

11

ST-Macro/micros

T- Macro/micros L-Macro/micros

1 Inch

L2BL (L-direction)

L2BST (ST-direction)

1 Inch

L2BT (T-direction)


Product Heat

Treatment Test

Direction UTS (ksi)

0.2% YS (ksi)

% Elongation

% RA C(T) Fracture

Toughness (ksi √inch)

First Trial Ratio 18.81

Temperature 2130⁰F

Production heat treated

L 141.7 128.5 11 25.5 78.8

L 142.1 128.1 11 26

2nd Trial Ratio 33.8

Temperature 2140⁰F Back End

As extruded + Lab heat treatment

L 142 128.5 13.5 30.5 79

Ratio 33.8 Temperature 2190⁰F

Back End

Production heat treated

L 139 123 13 25.5 75.5

Extrusion from Wrought Billet

L 143 127 14 26

Minimum Value as per AMS 4935H spec

L 130 120 10 20

Mechanical Properties of L Shaped Ti-6Al-4V

Extrusions made from ConCast Ingots

12 Titanium 2011 October 2-5, 2011 RTI Proprietary Information


Bars Rolled from

ConCast Billets

2”

1.5”

1”

0.5”



Photomicrographs of Ti-6Al-4V

Bars Rolled from ConCast Ingot,

Transverse Direction

0.5” Ø, 98% Reduction, = 8.32 1” Ø, 94% Reduction, = 5.55




Photomicrographs of Ti-6Al-4V

Bars Rolled from ConCast Ingot,

Longitudinal Direction




Product % +

Reduction UTS (ksi)

0.2% YS (ksi)

% Elongation

% RA

0.5" Ø 98 152.0 142.0 14.7 43

1" Ø 94 143.0 134.0 15.5 42.5

1.5" Ø 86 145.2 135.3 14 36

2” Ø 75 144.0 134.0 14.5 36.5

MMPDS Data (AMS 4928)* 135-140 125-131 10 25

Longitudinal Mechanical Properties of the Ti-6Al-4V Bars Rolled from ConCast Ingots

*Range includes bar sizes from 0.5”-2” Ø

Heat treatment: 1350F anneal for 2 hours and rotary straightened

16 RTI Proprietary Information Titanium 2011 October 2-5, 2011

50

60

70

80

90

100

110

120

130

140

150

100 1,000 10,000 100,000 1,000,000 10,000,000 100,000,000

Maxim

um

Str

ess

, ksi

Fatigue Life, Cycles

Fatigue Life of Smooth ConCast Bar Specimens

(Mean Stress = 0 ksi, 0.5" and 2" Bars)

ConCast 0.5" diameter Bar ConCast 2" diameter bar MMPDS Data

The fatigue life of the smooth ConCast bars at this mean stress level

is comparable to or better than MMPDS data 17

RTI Proprietary Information Titanium 2011 October 2-5, 2011

0

10

20

30

40

50

60

70

80

10000 100000 1000000 10000000 100000000

Maxim

um

Str

ess

, ksi

Fatigue Life, Cycles

ConCast 0.5" diameter Bar ConCast 2" diameter Bar MMPDS Data

Fatigue Life of Notched (Kt=2.43) ConCast Bar Specimens

(Mean Stress=0 ksi, 0.5” and 2” Bars)

The fatigue life of notched ConCast bars at this mean stress level is comparable to MMPDS data

18 RTI Proprietary Information Titanium 2011 October 2-5, 2011


Summary


• Continuous casting is an effective way to reduce

the cost of certain types of titanium products

• Mechanical properties of castings, extrusions and

bars made from ConCast ingots meet specification

requirements

• Efforts for commercialization of ConCast products

are in progress

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