This paper describes the results of the European project "THIXOCOMP" within the 5th framework programme concerning the material selection and development of tools for the thixoforging of steels. Due to high process temperatures, special requirements are necessary regarding the tool material and the tool concept. Special tool coatings (High Velocity Oxi Fuel, HVOF and Plasma Spray, CAPS) with high strength, high corrosion and oxidation resistance were deposited on substrate materials 1.2367, 1.4841 and 2.4631 to improve the properties of the tool materials. Different laboratory tests were performed to investigate the suitability of the tool systems. Pull tests, micro-hardness measurements, high temperature corrosion tests and spalling resistance tests were performed to investigate the adhesion of the coatings. The investigation of the thermal shock loading on the coated samples indicated a clear dependence on the base material. Both coatings on the base materials 1.2367 and 1.4841 were removed completely in the spalling resistance tests, so that even in the coated state, they are not suitable as tool materials for the thixoforming of steel. The combination of 2.4631+HVOF provided the best results. Afterwards, thixoforging trials were performed with the nickel-based alloy, 2.4631. After 30 trials at 1290°C (HS6-5-3), the tool showed no macroscopic damages, whereas a deformation of the press channel was already visible after eight forming trials at 1430°C (100Cr6).
[1]
Rainer Telle,et al.
Model Tests and Analysis of Corrosion Resistance of Ceramic Tool Dies for Steel Thixoforming
,
2004
.
[2]
Wolfgang Bleck,et al.
Investigation of Thixoforged Damper Brackets made of the Steel Grades HS6‐5‐3 and 100Cr6
,
2005
.
[3]
A. Bührig-Polaczek,et al.
Casting of High Alloy Steels in the Mushy State
,
2004
.
[4]
Dirk Abel,et al.
An automated Thixo‐Forging Plant for Steel Parts
,
2004
.
[5]
Jochen M. Schneider,et al.
Adhesion and Thermal Shock Resistance of Al2O3 Thin Films Deposited by PACVD for Die Protection in Semi‐solid Processing of Steel
,
2004
.
[6]
Bernd-Arno Behrens,et al.
Thixoforging of Steel Using Ceramic Tool Materials
,
2004
.
[7]
Reiner Kopp,et al.
Characterization of Steel Thixoforming Tool Materials by High Temperature Compression Tests
,
2004
.