1. ATAS Metallurgical Process Control VI Foundry Conclave, Coimbatore 2013-03-02

2. Metallurgical Process control systems

3. Basic needs of a foundry
Improved customer confidence
Low environmental impact
Improved financial results
Competitive edge
High Yield
Low direct costs
Process stability (Reliability)

4. The purpose of process control
World Class
Automate
Simplify
Control
Chaos

5. Do I have all data needed to control my process?
Day 1
C = 3,4 %
Si = 2,1 % , 1380°C
Rejection rate = 2,0 %.
All measured data OK!
Day 2
Rejection rate = 12,0 % ?

6. The purpose of process control
You get what you measure
If it´s not measured it cannot be improved

7. Chemical & Thermal Analysis
The spectrometer shows the amount in % of different elements in the melt.
The metallurgical key temperatures show the total effect of elements, oxides, silicates, dissolved oxygen, combined oxygen and other gases in the melt.
It is the effect that is important to know for process control!

8. Disadvantages of only using the spectrometer
You will not receive any information about ….
created compounds
oxides, silicates, sulphides etc
chemical reactions
nucleation or precipitation of graphite
the dynamics of solidification

9. The metallurgical “Fingerprint”

10. Controlling the process with 6 Basic parameters
Liquidus
Recalescence
Solidus
Graphite factor 2
Graphite factor 1
Low eutectic

11. Liquidus - TL

12. Adjusting CEL with Spectro
If C and Si are within limits then the iron is considered to be OK.
Example:
C = Si = P =
CEL = C + Si/4 + P/2. CEL min=3.83 CEL max=4.05
Variation +/ Variation in TL = 1168 – 1193 = 25 C
RISK FOR DEFECTS

13. TElow = f ( Nucleation status, Disolved Oxygen & Oxides )
Low eutectic - TElow
TElow = f ( Nucleation status, Disolved Oxygen & Oxides )

14. Thermal parameters TELow
TElow, The low eutectic temperature (a high value is essential).
If TElow is too low then the nucleation is too low. Risk for chill in corners and thin sections. Risk for undercooled graphite shapes.
TElow
TElow > 1135°C
Primary Carbides
FREE
TElow ≤ 1135°C
PRESENT

15. Recalescence - R
R = f ( Nucleation rate + Eutectic growth )

16. GRF 1 = f ( under cooling, precipitation speed, amount of graphite)
Graphite factor 1 – GRF1
GRF 1 = f ( under cooling, precipitation speed, amount of graphite)

17. Thermal parameters GRF1
GRF 1, Graphite Factor 1 (a medium value is good).
If too low it is an indication that the carbon content might be too low especially if R is low or normal. It also indicates that the precipitation of graphite is lower than normal, which might be due to bad nucleation. A low GRF 1 indicates a risk for micro-shrinkages.
GRF1
75 < GRF1 < 120
Porosity FREE
GRF1 ≤ 75
Porosity
GRF1 > 120
Chunky

18. GRF 2 = f ( Graphite shape & amount )
Graphite factor 2 - GRF2
GRF 2 = f ( Graphite shape & amount )

19. Thermal parameters GRF2 GRF2 > 55 35 ≤ GRF2 ≤ 55 GRF2 < 35
MICROSRHINKAGE
PRESENT
35 ≤ GRF2 ≤ 55
MICROSHRINKAGE
FREE
GRF2 < 35
DEGENERATED
GRAPHITE
Thermal parameters

20. Solidus - TS
TS = f ( Segregation, Mg )

21. Controlling shrinkages
T,°C
Dendrites
Eutecticum S1 S2 S3
t,s
Outher sunks
Macro Shrinkage
Micro shrinkage / Porosity

22. ATAS can detect problems long before they end up in the casting…
Stop
Correct
Improve
…and introduce a system for continuous improvement

23. First sample – Base iron DB
© NovaCast Foundry Solutions 2010

24. Second sample – Base iron DB
Optimal Base iron achieved!
© NovaCast Foundry Solutions 2010

25. Third sample – Uninoculated Final iron DB
© NovaCast Foundry Solutions 2010

26. Fourth sample – Inoculated Final iron DB
Optimal Final iron with low Mg- additions!
© NovaCast Foundry Solutions 2010

27. Summary
ATAS provides important control of the metallurgical process, helping foundries to better understand the metallurgical implications that are affecting the final product quality
© NovaCast Foundry Solutions 2010

28. Raw Material Selection Chemical Composition Preconditioning
Summary
With ATAS the foundry can control and adjust vital processing steps such as:
Raw Material Selection
Chemical Composition
Preconditioning
Magnesium Treatment
Inoculation
© NovaCast Foundry Solutions 2010

29. ATAS Alloy Database Contains specific parameters for different
stages in the process, from Base to Final iron

30. Conclusion Establish a cost effective Charge mix
Reduction of Inoculation
Reduction of Rejection Rates

31. Conclusion Improved Machinability
Consistent quality, mechanical properties and microstructure

32. Conclusion Provides Evaluation Provides Statistics
Provides Data Management

33. Tailored solutions
Process control by ATAS can be tailored to become a part of the
everyday process at any foundry, prepared to be connected to
demanding networks and complex server systems
Man + Machine + Method

34. …measures the effect of all elements and compounds
…creates a system for continuous improvement
…ensures stability of the metallurgical process
…essential for Ductile Iron production
…can be profitable within 6 months
…is used by people

35. ATAS Metallurgical Process Control VI Foundry Conclave, Coimbatore 2013-03-02
THANK YOU