This report describes an off-the-shelf Orbital Tube Welder that can be easily used to melt and resolidify almost any electrically conductive material. This can be done on a KC-135 Aircraft within the microgravity period of one parabola. Melt sizes 3 mm diameter by 10 mm length and larger are feasible with most if not all materials. A highly reproducible, controlled, programmable heat and cool cycle can be provided. Sample measurements would have to be developed and could be as sophisticated or as simple as desired. These could include: optical and thermocouple temperature measurements, Peltier pulser for marking the solidification fronts, dimensional changes and whatever. Sample heat flows could be fixed over a very wide range being limited mostly by the cooling period, the desired sample size, and the 20 sec microgravity period of the KC-135 Aircraft parabola

Poorman, Richard M.

English

NASA Technical Reports Server

NASA 
Technical 
Memorandum 
NASA TM - 86590 
RAPID MELT/QUENCH FURNACE USING 
COMMERCIALLY AVAILABLE HARDWARE 
Richard M .  Poorman 
Spacelab Payload Project Office 
March 1987 
(NASA-Tf l -e6590)  ELLPIC BEL!Z/ClJENCB FURNACE N87-20431 
O S l l G  CGEI!EBCIALLY BVAlLIABLE HAZIC.CABE (NASA) 
74 P CSCL 22A 
Unclas 
63/29 45446 
b NASA 
National Aeronautics and 
Space Ad m I n ! s t r a t I o n 
George C. Marshall Space flight Center 
MSFC . Form 3190 (Rev. May 1983) 
https://ntrs.nasa.gov/search.jsp?R=19870010998 2020-03-20T11:17:45+00:00Z
TECHNICAL REPORT S T A N D A R D  TITLE PAGE 
1. REPORT NO. 12. GOVERNMNT ACCESSION NO. 13. RECIPIENT'S CATALOG NO. 
7. AUTHOR(S) 
Richard M. Poorman 
9. PERFORMING ORGANIZATION NAME AND ADDRESS 
NASA TM-a6590 I 
4. T I T L E  AND S U B T I T L E  15. REPORT DATE 
8 .  PERFORMING ORGANIZATION REPOR r I 
10. WORK UNlT NO. 
Rapid Melt/Quench Furnace Using Commercially 
A vai lable Hard ware 
George C.  Marshall Space Flight Center 
Marshall Space Flight Center, Alabama 35812 
1 2 .  SPONSORING AGENCY NAME AND ADDRESS 
1 1 .  CONTRACT OR GRANT NO. 
1 3 .  TYPE OF REPORT e PERIOD COVERE[ 
il F. (of t h h  wee) 2 1 .  NO, OF PAGES 
14 
National Aeronautics and Space Administration 
Washington. D.C. 20546 
22. PRICE 
NTIS 
Technical Memorandum 
19. SECURITY CLASSIF.  (d t h h  ropmt) 
l?'gc!a.i!'ipd 
I 
1 5 .  SUPPLEMENTARY NOTES 
Spacelab Payload Project Office 
20. SECURITY CLA 
Unclassified 
16, ABSTRACT 
This report describes an off-the-shelf Orbital Tube Welder that can be easily used to melt m d  
resolidify most any electrically conductive material. This can be done on a KC-135 Aircraft within 
the microgravity period of one parabola. Melt sizes 3 mm diameter by IO mm length and larger are 
feasible with most if not all materials. A highly reproducible, controlled. programmable heat and 
cool cycle can be provided. Sample measurements would have to be developed and could be as 
sophisticated or as simple as desired. These could include: optical and thermocouple temperature 
measurements, Peltier pulser for marking the solidification fronts. dimensional changes and whatever. 
Sample heat flows could be fixed over a very wide range being limited mostly by the cooling period. 
the desired sample size, and the 20 sec microgravity period of the KC- I35 Aircraft parabola. 
17. KEV WORDS 
Microgravity, Melt, Resolidify, 
Composite materials, 
KC- 1.35 P,i:c:aft 
Directional Solidification 
18. DISTRIBUTION STATEMENT 
Unclassified/Unlimited 
TABLE OF CONTENTS 
Page 
................................................................................................ I 
I 
I 
2 
BACKGROUND 
OBJECTIVE 
APPROACH 
SAMPLECONFIGURATION 
...................................................................................................... 
...................................................................................................... 
................................................................................. 
...................................................................................... O N  R O A R D T H E  KC-135 3 
.......................................................................................... 4 
7 
9 
FEASIBILITY TESTS 
CONCLUSION 
APPENDIX A 
.................................................................................................. 
.................................................................................................... 
iii 
Figure 
I .  
2 .  
3. 
4. 
LIST OF ILLUSTRATIONS 
Title h g c  
2 
3 
.................................................................................... 5 
Rapid melthapid quench configuration.. ............................................................ 
Sample No. 4 - aluminum alloy 4043 longitudinal cross section ................................. 
Aluminum samples 
Copper and tungsten samples ........................................................................... 6 
iv  
TECHNICAL MEMORANDUM 
RAPID MELT/QUENCH FURNACE USING COMMERCIALLY 
AVAILABLE HARDWARE 
BACKGROUND 
Microgravity science experimenters are regularly melting and resolidifying materials in 
various gravity fields. Drop Tube, Drop Tower, and Aircraft are the only N A S A  facilities providing 
microgravity environments today. These facilities provide relatively short low-gravity periods. And, 
as one might expect, melting and resolidifying in shorter and shorter low-gravity periods are increas- 
ingly difficult. Smaller samples tend to ease the difficulties in accomplishing melthesolidification 
within short low-gravity periods. 
Recently, an interest was expressed in melting and resolidifying in one low-gravity parabola 
aboard a KC- I35 Aircratt. This interest was primarily for materials which would have segregation 
when they were molten. I t  includes a wide variety of materials, but mostly, metallic, and/or com- 
posite materials. 
Hahically. t o  process such materials in one KC- I35 parabola means melting and resolidifying 
in approximately 20 sec or less. Most investigators want large samples and directional solidification. 
This report will present an approach for accomplishing such material processing. 
OBJECTIVE 
The objective is to melt and resolidify a sample of material within the 20 sec low-gravity 
period Ilown by a KC-135 Aircraft. Sample diameters of 2 to 5 mm and lengths of IO to 20 mm 
were given by one experimenter. 
APPROACH 
The approach here is to surround the sample with relatively large heat sinks. The sample itself 
would be rapidly heated near its center with an intense energy source. This source might be a laser, 
focused thermal radiation. electron beam, and/or conventional inert gas tungsten arc. Feasibility tests 
have been made using the latter. 
These tests included the use of a commercial Orbital Tube Welder. Several different coni- 
panies supply highly refined Orbital Tube Welders which totally enclose the work piece. Attached is 
control the weld parameters are noteworthy. In particular, the weld arc can move around the sample 
a brochure o f  such a cnrnmercia! u n i t .  f]exibi!iQl 3r.d its capabi!i:y :G ;ig{;;<;usly 
in a programmable manner at speeds up to 60 rpm. Weld current is timed and programmed with up 
to tour different current levels. Arc length and position are adjustable and all are very reproducible as 
required in complex tube welds of highly reactive materials. 
SAMPLE CONFIGURATION 
The sample is conceived to be a rod between two large rod-shaped heat sinks (Fig. I ) .  This 
configuration can provide directional solidification as shown in the longitudinal section (Fig. 2). 
Directional solidification is often considered to be desirable. By reducing the heat flow down the rod, 
solidification from the outside toward the middle can predominate, e.g., nondirectional sol i d i  f i c a t i  on. 
Thus, a wide variety of solidification patterns can be provided by controlling the heat flow both to 
and from the sample. 
ON BOARD THE KC-135 
The Orbital Tube Welding system can be readily adapted to operations onboard a KC- 135 
Aircraft. The 100 V,  60 Hz, 20 A circuit, on board, will provide adequate power for the proposed 
100 A DCSP weld currents. The 90 Ib power supply, tube weld head, and remote pendant can 
provide easy control. Sample changes during flight between parabolas would be readily 
accomplished. 
HEAT SINK-\ 
Figure 1 .  Rapid melthapid quench configuration. 
2 
ORIGINAL PAGE IS 
oFpooRQuAury 
3 
./ ' 
FEASIBILITY TESTS 
Preliminary tests were made with aluminum. stainless steel. and tungsten. These tests were 
made with a standard GTA welding torch. While supporting a long rod away from the center and 
in a horizontal position, an arc was established at the center. The torch was hand held in a vertical- 
down position. Using various arc currents, it was readily apparent that samples of aluminum. stain- 
less steel and tungsten, 3 mm diameter and larger, could be melted in less than 10 sec using less 
than 100 A DCSP. 
Arrangements for demonstration melts were then made with one supplier of Orbital Tube 
Welders. All samples were made by fitting the sample rod with aluminum heat sinks o n  each end. 
The sample rods were 90 mm long. The fitted heat sinks were 13 mm diameter by 25 mm long 
aluminum. This left a free sample length of 45 mm. 
Sample rods of aluminum, copper and tungsten were prepared. Table I shows the heat and 
test parameters used. All heating periods were 5 sec except sample No.  IO. Sample N o .  I O  was 
heated 6 sec. The approximate nugget size is also shown in Table I .  
Figures 3 and 4 show the resolidified surface appearance 01' sample Nos.  4. 6. 8. 9. mid IO. 
The arc path is clearly identifiable on all materials except tungsten. And of' course. the nugget x i x  
was small enough that the surface tension held the melt against the gravity field ( I-g). That is. dl 
except sample No.  10; surface tension did not hold and the sample separated in the I'inal stagcs 01' 
me It ing . 
TABLE 1 .  
SAMPLE No. 
1 
2 
3 
1 
5 
6 
7 
8 
9 
10 
MATERIAL 
ALUhlIBUhl 
ALUY I NUN 
ALUbIIBUhl 
ALUhI I SUM 
ALULIINULI 
A LUhl I h' UBI 
COPPER 
COPPER 
TUNGSTES 
TUNGSTE?; 
ARC LENGTH 
6.35mm 
12 .  Imm 
1 2 . 4 m i  
1 2 . 4 m m  
1 2 . 4 m m  
1 2 . 4 m m  
1 2 . 4 m m  
1 2 . 4 m m  
12.  4mm 
1 2 . 4 m m  
CLRREST 
30 AMP. 
30 MIP. 
30 AYP. 
50 A!lP. 
50 AIIP. 
73 A!dP. 
75 X I P .  
75 .VIP.  
30 AIIP. 
100 .AMP. 
RPII 
2 4  
2 3  
8 
-
2 4  
24 
24 
2 3  
24 
24 
2 1  
P O S I T  I O S  
HOR. 
HOR. 
IlOR. 
YLRT,  
!{OR. 
L t i : T .  
L t R T .  
HOR. 
VERT. 
VERT.  
SUGGET S I Z E  
4 . 7 6  s 5.3:311;111 
4 . 7 6  s G.2mm 
4 . 7 6  s 7.lmm 
-1 . 76 A 18. -4ir,rri 
6 . 2  s 5.7mm 
G . 2  s 1 3 . 9 m i n  
4 . 1  s 3.2mm 
4 .  1 s 1 .3 t r ,m  
3 . 2  x 2 . 8 m m  
3 . 2 m m  
S O T E S :  ARC LEKGTHS RESULTED I N  
SUGGET SIZES ARE S.4IIPLE 
VOLT.AGES OF 9 AND 11 YOLTS. (.ARGOS S H I E L D I S G  C A S )  ( D C L P )  
DIAMETER S SUGGET LESGTH I N  !JILI.I . \IETERS. 
ALL SAMPLES \$ERE MADE AT MERRICK E N G I S E E R I N G .  S , \ S f I V I L L E  O N A N O R B I T A L  TUBE h E L D L I I  
RPM IS THE RATE THE ARC MOVED AROUND THE S,\IIPLE ( R E V O L L T I O K S  PER M I S U T F ) .  
I 
ORfGWAL PAGE IS 
OF POOR QUALl'W 
. .  . .  
J . "  .% 
v, 
W 
1 n 
5 
v, 
w 
z 
4 
lx 
w 
a 
n 
6 
ORiGINAL PAGE IS 
Of  POOR QUALm 
The arc line will require some study. Electrode shape and material will be important 
parameters. A very pointed tungsten electrode was used in these tests and probably exaggerates the 
arc line. The 1.6 mm diameter electrode was sharp and had about 15 deg included angle on the arc 
end. 
CONCLUSION 
I t  seems readily apparent that an off-the-shelf Orbital Tube Welder can be easily used to melt 
and resolidify most any electrically conductive material. I t  can be done on a KC-135 Aircraft within 
the microgravity period of one parabola. Melt sizes 3 mm diameter by IO mm length and larger are 
feasible with most i f  not all materials. A highly reproducible, controlled, programmable heat and 
cool cycle can be provided. Sample measurements would have to be developed and could be as 
sophisticated or as simple as desired. These could include: optical and thermal-couple temperature 
measurements. Peltier pulserfor marking the solidification fronts, dimensional changes, and what- 
ever. Sample heat tlows could be fixed over a very wide range being limited mostly by the cooling 
period. the desired sample size. and the 2Osec microgravity period of the KC- 135 Aircraft parabola. 
7 
T H I S  PAGE INTENTIONALLY LEFT BLANK 
APPENDIX A 
9 
AUTOMATIC TUBE WELDER 
Dim Dim Dim 
Standard Sues A B C 
ModelSTW101 2 0 0 "  1 0 "  2 75" 
Model STW 102 2 35" 1 815" 3 875" 
(508cm) (254cm) (699cm) 
15 97cm) 14 61cml 19 84cm) 
MODEL PA-100-STW 
TubeDia 
Range 
'la" to 718" 
'I." 10 1 I?" 
runasten 750ki P--l
Location 
Clamp Latch 
Interchangeable 
Collets 
'Ground 
Contact 
. Handle 
' Flexible 
Cable 
I ModelSTW103 1 2350" I 2765"  I 575"  I 1" 103" I 
(597cm) (7 02cm) (1461cm) 
MODEL PA-100-STW The Weldlogic PA-100-STW tube weld power 
supply is designed lor automatic all position autogenous pulsed arc (T I  G ) 
weldinp of all weldable grades ol tubing The power supply has been 
housed in a portable yet rugged aluminum enclosure suitable tor site (ise 
and is conveniently powered by any 115VAC (200/220V AC available) The 
power supply is a very stable precise 100 ampere tranostor controlled 
solid state system All weld parameters are direct digital readout with a 
repealdbibty factor of _+ 100 with line voltage vanations 01 f 12% 
In operation the tubing is located in the collects of the STW series head 
and locked into position A view port in the top of the head provides 
verification 01 alignment 
By initiat/ng the SEQ START button the closed servo leed back 
precisely controls and monitors the entire automatic weld sequence 
lrom preflow through four independently adjustable timed weld currents 
into downslope and post purge The results are a high quality push 
button completely automatic orbital tube weld that can meet the most 
demanding welding criteria 
ORBITAL TUBE WELD HEADS 
tube welding power supply and control system IS desigried t o  be used with 
Weldlogic s S TW senes Orbital Tube Weld Heads Stand,iio w i d  heads 
accommodate tubing from 125" dia (3 2mm) to 3 00 t k i  (76mm) The 
weld heads listed are s tand~rd production models comb1 rimj ruggedness 
with precision Weldlogic also designs special applicatiail tube heads to 
meet your specific mechanical requirements 
REMOTE OPERATORS PENDANT An operators p t i m n t  control is 
provided with each PA 100 STW to assist in cases where the weld is localed 
out of immediate reach ol the power supply The operators pendant 
provides all the control functions lor the weld head and power supply 
remote sequencing The operators pendant control is supplied with 25' 
(77mj cable (control lunctions listed below) 
MANUAL WELDING 
operaled with J moue/ PA AOJ 3 loot operated current control This feature 
provides a very prLicticcil cdpability lor manual TlG use lor tacking 
or repair welding 
EXTENSION CABLES Optional extension cables are available lor a// 
accessories and *e/d heads 
The kt'e/d/og/c model PA 100 STtv 
The PA 100 STW tube welding system may be 
CON TU01 SPECIFICATIONS 
Size 12" T x  16" W x  21 " L  Switches 
Weight 9Olbs (40 7kg) 
Meters 0- 100 amps 
Thumbwheel 0-9 seconds upslope 
Digital 0.99% pulse width Toggle Swilches 
Switches 0-99 amps (level 1.2.3.4) F ~ O W  Meter 
PA-1OO-SW 
(304mm x 406mm x 533mm) 
0-50 V O ! ~  
0-99seconds(Level1.2.3.4/ Breaker 
REMOTE OPERATORS PENDANT 
1 99 pulses per second Push Buttons Sequence start 
0-99 amps bachground current Sequence stop 
0-9 seconds downslope Return to home 
0-99 seconds pre flow gas Jog 
0-99 seconds post flow gas Purge- MA N/AU TO 
0-9 seconds rotation delay 
0-99% tachometer speed control 
Pulsation ON/OFF 
(Speclllcallons subiecl 10 change) 
0-50 CFH 
Power ON/OFF; 20 F L. amps 
"Advancing th ELDLOGIC, Inc. 
Science of Welding" Automated Welding Systems 
9730VarielAvenue Chatsworth.Californ1a91~11 (818) 709-6006 Telex 3781686WELDLOGIC 
10 ORIGINAL PAGE IS 
O f  POOR QUALITY 
APPROVAL 
RAPID MELT/QUENCH FURNACE USING COMMERCIALLY AVAILABLE HARDWARE 
By Richard M .  Poorman 
The information in this report has been reviewed for technical content. Review of any inlor- 
mation concerning Department of Defense or nuclear energy activities or programs has been made by 
the MSFC Security Classification Officer. This report, in its entirety, has been determined to be 
unclassified. 
James A.(qbwney I11 J 
Manager, Spacelab Payload Project Office 
11 


Rapid melt/quench furnace using commercially available hardware

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