Kerphalite™ KF for Cores Kersand™100-400 for Mould

SPECIAL SAND FOR FOUNDRY Ankiros 2018

What is Kerphalite™KF & Kersand™100-400 ?

Philippe Diaz 2

Kerphalite™ KF & Kersand™100-400 are both “andalusite” mineral.

Kerphalite™ KF & Kersand™ 100-400 are an alternative to traditional natural sands such as silica sand and , chromite or zircon for cores and molds production.

Key properties are:

High Refractoriness (capability to withstand high temperature without melting or softening)

Low Thermal Expansion

High Thermal Conductibility

Suitable for all organic binders

Total compatibility with Silica Sand

Kerphalite™KF & Kersand™100-400 – Production

Philippe Diaz 3

Kerphalite™KF & Kersand™100-400 requires many processing stages to achieve the quality required by the foundry application

Mining and Processing plant is located in France

18 years of extraction rigth

Kerphalite™KF & Kersand™100-400 – Chemistry

Philippe Diaz 4

Both are pure aluminosilicate : Al2O3·SiO2

Typical Chemical composition :

Typical Chemical comparison :

Kerphalite™

KF

Kersand™

100-400

Al2O3 61% 59%

SiO2 38% 39%

Fe2O3 0,5% 0,75%

K2O + Na2O + MgO + CaO < 0,5% < 1%

% Al2 O3 SiO2 MgO CaO Fe2O3 K2O TiO2 ZrO2 Na2O Cr2 O3

Kerphalite™ KF 60,8 38,1 0 0 0,45 0,1 0,1 0 0,1 0

Kersand™ 100-400 59,1 38,5 0,15 0,1 0,75 0,3 0,25 0 0,15

Zircon Sand 0,8 32 0 0 0,1 0 0,2 63,5 0 0

Chromite Sand 14,8 0,9 9 0 30,4 0 0,5 0 0 43,6

Ceramic Beads 60% 60,1 36,9 0 0,2 1,2 0,1 0,5 0,1 0,5 0

Kerphalite™KF & Kersand™100-400 – Refractoriness

Philippe Diaz 5

Due to the high alumina content (> 60%) and low alkalis level vs ceramic beads 60%

Melting point of Kerphalite® KF exceeds 1800°C

Kerphalite™KF & Kersand™100-400 – No risk of Fayalite defect

Philippe Diaz 6

Fe2O3 content in chromite blended with silica sand can provide a tremendous drop of the melting point.

Sintering phase occur at 1208°C

These is fayalite

Kerphalite™KF & Kersand™100-400 – Chromite + Sand defects

Philippe Diaz 7

Chromite is mainly recommended when an effective magnetic separation system available.

If not, following sand penetration could occurred.

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0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100%

% o

f co

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Amount of Chromite

Impact of Chromite on Metal Penetration of Silica sand core Gertsman Test - Carbon steel E20-40M

Poyet, P; Chevriot, R - 46th international Foundry Congress - Madrid 1979

Kerphalite™KF & Kersand™100-400 – Thermal Expansion

Philippe Diaz 8

Thermal expansion is the key point to reduce veining defects

Both shows a low thermal expansion rate, close to zircon and significantly lower than silica sand, olivine & chromite

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dl/

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Temperature °C

Quartz

Olivine

Chromite

Zircon

Kerphalite &Kersand

Kerphalite™KF & Kersand™100-400 – Cooling Effect

Philippe Diaz 9

We have introduced relevant parameter in Software Magma5

We have designed a simple but massive casting roller (40cm diam) with central core (4cm diam).

The simulated curves have been taken from the center of core.

Results

Cooling behavior of Kersand is performing as chromite

Other sands like Treibacher Alodur ® WRG performe far better than chromite !!

Kerphalite™KF & Kersand™100-400 – Thermal Resistence test 1/2

Philippe Diaz 10

Thermal resistance test allows to simulate thermal radiations & convections

during pouring time

Moving

support

1500°C

Sand Sample

Furanic binder

1500°C Thickness: 5mm

Final temperature is reached in about 2 minutes

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T [

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Kerphalite™KF & Kersand™100-400 – Thermal Resistence test 2/2

Philippe Diaz 11

Kerphalite™ KF & Kersand™100-400 doesn’t show any melted phases at 1500°C

The blend with 50% of silica sand increases the melting phase but allows significant improvement vs pure silica

100%

Kerphalite & Kersand

100%

Silica Sand

Mel

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ase

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Melted Phase after Thermal Shock 2 to 20 min 1500°C - Furanic Resin

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% Kerphalite KF

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20 min

Kerphalite™KF & Kersand™100-400 – Heating Microscope

Philippe Diaz 12

Heating microscope chart below shown us, at 3 different % of shrinkage, the temperature of softening.

Kersand™ 100-400 as Kerphalite™KF perform well and much better than mullite beads e.g.

Kerphalite™KF & Kersand™100-400 – Reclaimed level & LOI

Philippe Diaz 13

Courtesy of Omega

Yield recovery between 77% and 82% of Kerphalite KF recovered.

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KF 100-400As received

KF100-400Before USR

KF100-400After 1stPass USR

1st PassUSR

re-check

LOI

LOI

LOI

Kerphalite™KF & Kersand™100-400 – Reclaimed PSD and Sphericity

Philippe Diaz 14

Courtesy of Omega

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1000 710 500 355 250 180 125 90 63 Dustpan

Kerphalite KF 100-400 as received -AFS 64

Kerphalite KF 100-400 after 1 passUSR - AFS 71

Kerphalite™KF & Kersand™100-400 – Bending Strength

Philippe Diaz 15

Bending Strength in Mpa on various materials.

In the same lab conditions.

furane

Sodium

Silicate

CO2

Phenolic

Alkalin

Phenolic

Urethane

Self Set

Material* 24 hours 24 hours 24 hours 24 hoursAs

Gassed24 hours Hot Cold

European Silica Sand 4,5 2,2 1,9 3,6 4,3 5,2 6,4 8,8

Kerphalite KF 100-400 3,8 2 1,8 3,2 3,3 3,8 4,5 5,6

Kersand 100-400 3,5 2 1,7 3 3,2 4,1 5,5

ImerBeads 45AFS 4,6 2,3 2 3,5 4,9 6,2 6,7 9,2

Clayrac F45 100-400 3 1,9 4 5

* Blended with 50% silica sand

Phenolic Urethane

Cold Box

Pre Coated Sand in

Mpa

Kerphalite™KF & Kersand™100-400 – Differents Grades

Philippe Diaz 16

AFS 50

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425µ 300µ 212µ 150µ 106µ 75µ 53µ

AFS 60

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425µ 300µ 212µ 150µ 106µ 75µ 53µ

AFS 70

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425µ 300µ 212µ 150µ 106µ 75µ 53µ

AFS 100

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425µ 300µ 212µ 150µ 106µ 75µ 53µ

All usual AFS grades are available and possibly designed for special needs.

Both have the same bulk density close to silica sand.

You can produce 40% more cores, using Kerphalite or Kersand vs chromite or zircon

20 tons

Kerphalite™KF & Kersand™100-400 – Bulk density 1/2

Philippe Diaz 17

Kerphalite KF

12,5 m3

Kersand™

7,4 m3

Zircon

Based on previous slide, we take an example of foundry which is buying 300tons/ year of chromite

The Volume of chromite bought is 111m3

For same volume, that’s means, same quantity of core & mold , you ONLY need to purchase 178 tons per year instead of 300Tons of chromite

Resin consumption is also a sensitive topic

As all resin setting are based on sand , we weight resin/catalyst & sand at the screw of mixer

So, we should calculate on weight = Tons/year.

Even using 40% more resin with KERPHALITE !!

Foundry Manager introduce less resin in his sand reclamation => Less gas to remove during pouring

Purchasing manager will save 17% on total binder cost.

Kerphalite™KF & Kersand™100-400 – Bulk density 2/2

Philippe Diaz 18

Type of Sands DensityQuantity of Sand needed

in Tons per year

Equivalent in

Volume in m3

Savings

in tons

CHROMITE 2,7 300 111,1 0

KERPHALITE KF 1,6 177,8 111,1 122

Sands % of resinResin needed

per Year (en Kg)Savings

CHROMITE 1,00% 3000 0

KERPHALITE KF 1,40% 2489 -17%

Kerphalite™KF & Kersand™100-400 – Summaries

Philippe Diaz 19

Kerphalite™ KF & Kersand™ 100-400 will respond to special core shop as

molding requirements :

Low Thermal Expansion High anti veining properties

Good Thermal diffusivity and Conductivity Relative good Chilling effect.

Very low level of Fe2O No risk of fayalite Defect, no sand penetration

High refractoriness - 58 - 60% alumina

PSD properly design for all type of core application

Acceptable sand reclamation level.

Low density 40% more cores produced

Aluminosilicate mining and processing in Europe.

Thanks for your attention