Silica Ceramics - Features and Applications of SiO2 Ceramics for Metal Casting by Morgan Technical Ceramics

Topics Covered

Background
Morgan Technical Ceramics Certech for Metal Casting
Features of Certech Metal Casting
Manufacturing of Certech Metal Casting
Application of P-33 Ceramics for Metal Casting
Chemical Composition of P-33 Ceramics for Metal Casting
Trace Element Analysis of P-33 Ceramics for Metal Casting
Cristobalite Content Range
Process Shrinkage (Mold to Fired)
Modulus of Rupture
Thermal Expansion of P-33 Ceramics for Metal Casting
Physical Properties of P-33 Ceramics for Metal Casting
Core - Metal Reaction
Leachability of P-33 Ceramics for Metal Casting
Hot Modulus of Rupture
Creep Test of P-33 Ceramics for Metal Casting

Background

Turn to Morgan Technical Ceramics Melbourne (MTC Melbourne), formerly Carpenter Advanced Ceramics, advanced zirconia ceramics for your toughest material problems. MTC Melbourne's zirconia offers ideal solutions for many difficult applications where wear, abrasion, impact, corrosion and high temperatures cause conventional materials to fail. MTC Melbourne's patented compositions and highly-controlled manufacturing processes ensure that you will be working with the strongest, toughest, most consistent Mg-PSZ that you can buy - anywhere. Try MTC Melbourne's zirconia today.

Morgan Technical Ceramics Certech for Metal Casting

The Certech business was founded in 1970. In 1994 it became part of Carpenter Technology Corporation and in March 2008 was acquired by Morgan Technical Ceramics’ parent company, The Morgan Crucible Company plc. Since its origins, Certech has been meeting the needs of the investment casting industry with a broad line of complex injection molded ceramic components. These ceramic parts are used during the investment casting of turbine engine blades and vanes for aircraft and power generation, aircraft hardware, pumps, valves and sporting goods.

Features of Certech Metal Casting

Ceramic cores allow the creation of internal cavities during the investment casting process that are too complex or too small to be “shelled”. This allows turbine engine blades and vanes to be cast to size with complex cooling passages, which allow engines to operate at higher temperatures with greater efficiency. Ceramic cores are also used to create undercuts and hosels in golf clubs, pump impellers, valve bodies, and fuel system mixing components.

In addition to ceramic cores, Certech manufactures silica cores, porous ceramics and various foundry supplies such as pouring filters, cups, snouts, collars, funnels and extruded diameters. Decorative ceramics are also produced, including jewelry, picture frames and ornaments.

Manufacturing of Certech Metal Casting

Certech manufactures these products using a proprietary low-pressure injection molding process and a proprietary firing process, which have been specifically designed with high volume and short lead-time in mind. This allows Certech to generate sample volumes as quickly as five days, and routinely produce production volumes with a two-week lead-time. Another advantage of this the proprietary Certech process is that it is extremely low wear, allowing hardened steel dies to routinely produce in excess of 100,000 cores.

Application of P-33 Ceramics for Metal Casting

High silicia core type with intermediate particle size distribution and excellent high temperature stability. Used for DS and SX applications where there are blind passages and core leachability is a concern.

Chemical Composition of P-33 Ceramics for Metal Casting

The chemical composition of the P-33 ceramic for metal casting is outline in the following table.

Table 1. Chemical composition of P-33 ceramic for metal casting

Name

Formula

Typical %

Silica

SiO2

96.0

Zircon

ZrSiO4

1.5

Alumina

Al2O3

1.5

Other

-----

1.0

Trace Element Analysis of P-33 Ceramics for Metal Casting

The trace element analysis of the P-33 ceramic for metal casting is outline in the following table.

Table 2. Trace element analysis of P-33 ceramic for metal casting

Element

Symbol

Typical ppm

Iron

Fe

<900

Bismuth

Bi

<0.2

Lead

Pb

<1.0

Silver

Ag

<10.0

Antimony

Sb

<5.0

Tin

Sn

<1.0

Zinc

Zn

<50.0

Cristobalite Content Range

The cristobalite content range of the P-33 ceramic for metal casting is outline in the following table.

Table 3. Cristobalite content range of theP-33 ceramic for metal casting

Property

Typical %

After Fire

8.0

After 30 minutes @1530°C

57.0

Process Shrinkage (Mold to Fired)

The process shrinkage of the P-33 ceramic for metal casting is outline in the following table.

Table 4. Process shrinkage of the P-33 ceramic for metal casting

Property

Typical %

Length

1.25

Chord (width)

1.50

Modulus of Rupture

The modulus of rupture of the P-33 ceramic for metal casting is outline in the following table.

Table 5. The modulus of rupture of the P-33 ceramic for metal casting

Property

Typical p.s.i.

@RT

2000

@RT after 1 hour @1530°C

670

@1475°C

5160

Thermal Expansion of P-33 Ceramics for Metal Casting

The thermal expansion of the P-33 ceramic for metal casting is outline in the following table.

Table 6. The thermal expansion of the P-33 ceramic for metal casting

Property

Typical

@1000°C (x10-6/°C)

1.25

Physical Properties of P-33 Ceramics for Metal Casting

The physical properties of the P-33 ceramic for metal casting is outline in the following table.

Table 7. The physical properties of the P-33 ceramic for metal casting is outline in the following table.

Property

Typical

Bulk Density

1.60 g/cc

Apparent Density

2.30 g/cc

Porosity

30.0%

Absorption

19.0%

Core - Metal Reaction

Compatible with most DS and SX alloys

Leachability of P-33 Ceramics for Metal Casting

30% boiling KOH
30 grams sample
15 minutes
100% leached

Hot Modulus of Rupture

Heat bars @ 300°C/hour to 1550°C. Hold for 1 hour. Cool @ 15°C/minute to:

Temperatures

MOR

1250°C

5411 p.s.i.

Creep Test of P-33 Ceramics for Metal Casting

RT to 1550°C @ 300°C/hour. Hold for 1 hour. Cool at 600°C/hour.
Test bar dimensions: L-6", C/W -1/2", P-1/4"

Pressure (p.s.i.)

Deflection (inches)

150

0.540

Source: "Morgan Technical Ceramics Certech for Metal Casting", by Morgan Technical Ceramics

For more information on this source please visit Morgan Technical Ceramics

Date Added: Jan 12, 2009 | Updated: Jun 11, 2013
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