Post on 08-Apr-2017
DESIGN ASPECTS
The ceramic products must be reliable and cost must be optimized.
Ceramic materials are brittle and their strength is influenced by external stress.
Ceramic materials have low thermal conductivity and electrical
Avoid material accumulations and stress concentrations.
IMPORTANT DESIGN GUIDELINES Oval parts should be avoided. In the case of a circular
form a more homogeneous stress distribution will occur during loading.
Modular structures are preferred to lower component volume and improve reliability. The probability of having defects in a small volume is lower than in a large volume.
The ceramic component is prestressed with a compressive load, and hence tensile stresses are minimized. Choosing an arch instead of a beam converts tensile into compressive stresses in this case.
Separate the nodes. Avoid thick ends on moldings.
Avoid sudden changes in cross-sectional area.
• Provide large contact areas.
Avoid corners and sharp edges, around inner edges, and cut-outs.
Avoid long, sharp edges (risk of breakage).
APLICCATIONS
CERAMIC BRAKE DISKThe ceramic brake disk has
many advantages such as:
• Higher temperature strength than gray cast iron.
• Long lifetime, low wear• Corrosion resistance• Up to 70% reduced
weight
Let us briefly review the manufacturing steps to get a better understanding of this ceramic product.
• Mixing of carbon short fibers plus carbon powder plus resin.
• Pressing.• Carbonizing to a porous body
(900 to 1100°C).• Infiltration with liquid silicon
(1500 to 1600°C) reacting with matrix carbon.
HEATED OXYGEN SENSOR(HO2S)ZrO2 ceramic is the main material in this device.Used for controlling gasoline injection to minimize
emission behavior: The oxygen sensor (A) measures the
oxygen content in the exhaust gas, which leads to information about the gasoline-to-air ratio in the combustion chamber. This information, more or less an mV-signal, is forwarded to the control unit (B)