Download presentation
Published byDustin Armstrong Modified over 9 years ago
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
Similar presentations
© 2025 SlidePlayer.com. Inc.
All rights reserved.