At approximately 1015 Central time the airplane landed in a field during a forced landing following a total loss of engine power. The Airline Transport pilot, sole occupant of the airplane, was not injured. Visual conditions prevailed for the IFR positioning flight. According to the 7500-hour pilot, an unusual whining/hissing noise was heard from the engine at 6000 feet msl. As the airplane climbed through 8000 feet msl, the noise got louder and the inlet turbine temperature gauge fluctuated. Suddenly, a bang was heard and the engine quit. An in-flight restart was unsuccessful. The pilot then made an uneventful landing in a grass field. Examination revealed no structural damage to the airframe, however, molten metal was found inside the exhaust area of the engine.