Internal-combustion engine and process for applying a thermal barrier layer

US5722379A · kind A · utility

Assignee

• Daimler-Benz AG · DE

Inventors

• Klaus Binder · Munich, DE
• Karl Weisskopf · Welzheim, DE
• Patrick Izquierdo · Ulm, DE

Key dates

• Filing date: Nov 18, 1996
• Grant date: Mar 3, 1998
• Expiry date: Nov 18, 2016

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y10T428/1259
• WIPO field: Surface technology, coating
• WIPO sector: Chemistry

Abstract

This invention provides a porous thermal barrier layer for protecting parts of an internal-combustion engine having parts which are acted upon by combustion, and particularly by heat, and to a process for applying such a thermal barrier layer to these parts. The thermal barrier layer, which is formed of grains and/or fibers connected with one another on the exterior side, and is produced at least partially from a heat-resistant, temperature-shock-stable and abrasion-proof barrier material, has a heat penetration number defined by the following formula EQU b=.sqroot.p.cndot.C.cndot..lambda. with PA1 b: the heat penetration number of the thermal barrier layerin J.cndot.(Kcm.sup.2 .sqroot.s).sup.-1 !, PA1 p: the density of the thermal barrier layer in g/cm.sup.3 !, PA1 .lambda.: the thermal conductivity of the barrier material in W/cmK!, and PA1 C: the specific heat of the barrier material in J/gK! which heat penetration number is smaller than 0.25 J.cndot.(Kcm.sup.2 .sqroot.s).sup.-1 !, particularly smaller than 0.1 J.cndot.(Kcm.sup.2 .sqroot.s).sup.- !. Furthermore, grains and/or fibers which are hollow are used during the application of the thermal barrier layer, so that the total …