hot isostatic pressing technology for indian test blanket module fabrication
DESCRIPTION
Hot Isostatic Pressing Technology for Indian Test Blanket Module Fabrication. Dr. G. Appa Rao. Defence Metallurgical Research Laboratory Kanchanbagh PO, Hyderabad-500058, India. Email: [email protected]. 22 July 2008. Introduction. - PowerPoint PPT PresentationTRANSCRIPT
Hot Isostatic Pressing Technology for Indian Test Blanket Module Fabrication
Defence Metallurgical Research Laboratory Kanchanbagh PO, Hyderabad-500058, India.
Email: [email protected]
Dr. G. Appa Rao
22 July 2008.
Introduction
Selection of appropriate materials and fabrication technologies for various components for fusion reactors relies on trade-off between multiple requirements which are mainly driven by:
Economic Safety and Environmental effects
Materials:
Martensitic steels Non-Ferrous alloys Ceramics Vanadium alloys SiC/SiC Composites Ti and Cr alloys
Fabrication Technologies:
Cutting and machining Special welding techniques Investment casting Hot isostatic pressing (HIP)
Significance of HIP Technology
Implementation and joining of F/M steels are an important goal due to the complex geometry of the blanket modules.
Necessity for reducing the leak level and maintenance.
Advanced techniques based on solid or powder HIP are to be established
Principles of Isostatic Pressing
Pascal’s Law
Warm Isostatic Pressing(WIP) 1960
Hot Isostatic Pressing(HIP) 1955
Cold Isostatic Pressing(CIP) 1913
Isostatic Pressing
Temp. RT. ~300 ºC 2000 ºC
Pressuremedium
Water +oil Water +oilInert gas
Pressure 400 MPa 200 MPa 200 MPa
Powdercontainer
Rubber RubberSteel, Ceramic & Glass
Extent ofdensification
Green compaction Full density Full density
Hot Isostatic Pressing
HIP is a an innovative thermal treatment process subjects the material / component to a combination of high pressure and elevated temperature
HIP results in near theoretical density, uniform microstructure and consistent mechanical properties
HIPing Parameters:
Temperature : 0.7 - 0.9 Tm
Pressure : 100-200 MPaTime : 2- 4 h.
Details of HIP Equipment
Densification Mechanisms of HIPing
Particle rearrangement Plasticity Power-law creep and Volume and grain boundary diffusion
Stages of HIP Densification
HIP Diagrams
Applications of HIP Technology
Cladding
Diffusion Bonding
Consolidation of Encapsulated Powder
Densification of Metal castings
Specialized Applications:
Medical Implants
HIP of ultra fine Tungsten Carbide Cobalt Hard
Metals
Rejuvenation of Deteriorated Components
Formation and Control of Pores
Joining of Fusion Reactor Components
Cost Reduction Potential for a Selected Group of Superalloy
Parts
0
25
50
75
100
AS-HIPHIP+
H .W
Conventional Processing
Cost
Red
ucti
on
Pote
nti
al,
%
CIP and HIP Facilities at DMRL
(200 Dia. X 600 HT.) mm400 MPa
(100 Dia. X 200 HT.) mm, 200 MPa1450, 2000 ºC
(270 Dia. X 990 HT.) mm, 200 MPa1450ºC
(650 Dia. X 1200 HT.) mm, 200 MPa1450ºC
HIPing of Stainless Steel Powder
40 mm
1 2
100
200
300
400
500
600
700
40 %
490
200
85 %
660
280
Str
eng
th (
MP
a), D
uct
ility
YS UTS EL.
As-HIPed Spec.
G. Appa Rao and M.Kumar, Mater.Sci. and Technol. 1997
Superalloy 718 Integral Turbine Rotor
Stainless Steel Integral Turbine Rotor
Potential of HIP for Complex Shapes
HIP Diffusion Bonding of Materials
Material forms for HIP bonding:
Powder-powder
Powder-solid
Solid -solid
Advantages:
Similar and dissimilar material can be joined
Complex shape can be joined easily
Original microstructure remains intact
ODS and FRM can be joined
Joint integrity is better than that of conventional one
Microstructure of HIP Diffusion Bonded Materials
Shaft alloyDisk alloy
Cu-Solid
Cu-Powder
SS -Solid
SS-Powder
G. Appa Rao et. al, DMRL TR2000265 (2000)
Failure did not occur at the joint
1 21
10
100
1000
RT.
25%
1128735
25%
1320776
Pro
per
ty
YS (MPa) UTS (MPa) EL (%)
DMRL Spec.
1 21
10
100
1000
650°C
20%
1030618
25%
1117750
Pro
per
ty
DMRL Spec.
Mechanical Properties of HIP Diffusion Bonded Alloys
P/M(HIP) Diffusion Bonded Hardware (DMRL)
Ni-base superalloy components
Prototype thrust chamber clouseout
Overview of Blanket Module Fabrication(Literature)
Reduced Activation Ferritic Martensitic (RAFMA) steel is the structural material for TBMs
Fabrication concepts rely on plates with internal cooling channels
Main technologies for fabrication of TBMs:
Cutting and machining of semi finished products
Joining of parts to produce the plates with internal channels
Bending of cooling plates
Heat treatment to improve the structure and properties
Configuration Details of Blanket Module
(a) Two-Step HIPing Method:
First Wall Fabrication Procedures
Involves machined grooved plates
Use of Mo- alloy massive stiffening / supporting plates between the encapsulation and the FW/CP plates
HIPing at low pressure to achieve bonding at the Interface
Removal of encapsulation and Mo plates and drilling of channels
The FW is further HIPed at high pressure to achieve full bonding
Heat treatment, testing and evaluation
(b) Single High Pressure HIPing Method / HIP forming Process:
Involves insertion of round tubes in the rectangular grooves
Ends of the tubes are welded to the plates but the tubes are not closed
During HIPing, the tubes expand and conform to the grooves
Mo- alloy supporting plates are not required
Heat treatment, testing and evaluation.
(c) Rectangular Tube (RT) Process:
Involves diffusion welding of RTs. and cover plates
HIPing to improve the joint integrity
No need for stiffening plates
There is a scope for bending the RTs. and cover plates before HIPing.
Heat treatment, testing and evaluation
FW mock up manufactured by HIP forming ( top: parts before HIP;bottom: mock up after HIP, bending and marching.
Conclusions
Fabrication of test blanket modules (TBMs) is a technologically challenging task
Hot isostatic pressing (HIP) is a promising technology for fabrication of TBMs
Considerable expertise on several aspects of HIP technology is available at DMRL to address various issues in this field
Study on development of prototype TBM components can be taken up with the existing infrastructure.
Thank you