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This paper describes the development of a lead free, high temperature ceramic capacitor material having the base composition of (Na0.5 Bi0.5) TiO3. The goal is to modify this structure to create a material that has the relative permittivity of barium titanate with extended X7R-like properties to 250°C - an X14R. After an extensive compositional and theoretical modeling investigation a composition was selected and capacitors developed. The dielectric has a 1-kHz relative permittivity of ∼1200 with <±15% variation from -25 to +250°C and <5% loss from -55 to +250°C. These capacitors also have very low voltage coefficients, indeed they are positive at the low end of the temperature range, resulting in a combined TC-Vc capacitance variation 0%/-25% of nominal from -55 to +200°C with applied voltage stress from 20 to 260 V/mil.

Four different liner finishes were tested in a 7.6 L, 179 kW four stroke diesel engine. The primary motivator of the tests was to examine the effects of plateau honing on both rough (Ra ≈ .77 μm) and smooth (Ra≈.26 μm) liners. Measured effects were oil consumption, blowby, ring wear, and liner wear. The engine tests (some to 1100 hours) show that a smooth, plateaued liner offers the best finish for this engine with regards to oil consumption, ring wear, liner wear between the ring turnarounds, and volume of liner material lost due to wear.