METHOD FOR PRODUCING A COMPONENT FROM MAX PHASES

Abstract

For the first time, components can be produced from MAX-phases due to the use of an additive production method. A method for producing a component from MAX phases, in particular from Ti3SiC2 and/or Cr2AlC, in which an additive manufacturing process is disclosed. Powder is applied layer by layer and densified, the grain sizes of the powder lying at 10 μm to 60 μm, in which the scanning speed between the energy beam of the laser or electron beam and substrate with powder lies between 400 mm/s and 2000 mm/s, in particular at 1000 mm/s to 1500 mm/s, in which the power output is between 80 W and 250 W, in particular is 100 W to 170 W, in which a spot size of the energy beam lies between 30 μm and 300 μm.

Description

FIELD OF TECHNOLOGY

The following relates to a method for producing from MAX phases by means of an additive manufacturing process.

BACKGROUND

MAX phases are stoichiometric phases which, on the basis of the properties, are to be classified between metals and ceramics. On the one hand (metallic), they display good thermal conductivity and high thermal shock resistance, on the other hand (ceramic) they display extraordinary stiffness, corrosion resistance, high abrasion resistance and a low density. In addition, even at 1473° K.-1573° K., certain MAX phases still display significant creep and fatigue resistance.

These properties make the MAX phases of interest for high-temperature applications such as in gas turbines. Thus, blade tips may be reconditioned and armored with MAX phases. The low density and the resistances at high temperatures also make them appear to be suitable however for being used as materials for the blades.

Existing production routes:

1. Synthesizing the powdered basic constituents (transition metal+element of group A+carbon/nitrogen) by hot-isostatic pressing a workpiece is then produced from the solid body by machining limits in size and form.

2. A three-step process from a powder produced according to 1. of the correct stoichiometric composition: 3D printing of a green body (MAX phase+binder)+cold-isostatic pressing+sintering→an even more complex production route to create the powder+a complex three-step technique to ensure the final shaping.

The shaping of the MAX phases into components and the production are complex and laborious.

SUMMARY

An aspect relates to solving the aforementioned problem.

It is proposed to produce the MAX phases in near net shape or in net shape by means of selective laser melting (SLM).

This can be performed by two routes:

1) by means of mixed powders of the individual components of the MAX phase; or

2) by means of powder with the correct stoichiometry of the MAX phase.

The process data for the production process by means of the SLM process are as follows for the MAX phases, specifically however for Ti₃SiC₂ and Cr₂AlC: the grain size of the powder lies at 10 μm-60 μm, either gas-atomized or ground.

The following is proposed as a possible process window:

• • scanning speed: 400-2000 mm/s, preferably 1000-1500 mm/s
  • power output: 80-250 W, preferably 100-170 W
  • spot size: 30-300 μm.

In particular, a laser is used as the energy beam.

The processing of the alloy under a shielding gas leads to a low oxygen component in the matrix.

Claims

1. A method for producing a component from MAX phases, Ti3SiC2 and/or Cr2AlC, in which an additive manufacturing process is used, in which powder is applied layer by layer and densified, the grain sizes of the powder lying at 10 μm to 60 μm, in which the scanning speed between the energy beam of the laser or electron beam and substrate with powder lies between 400 mm/s and 2000 mm/s, in which the power output is between 80 W and 250 W,in which a spot size of the energy beam lies between 30 μm and 300 μm.

2. The method as claimed in claim 1, in which the powder has been produced by gas atomization.

3. The method as claimed in claim 1, in which the powder has been produced by a grinding process.

4. The method as claimed in claim 1, in which the method is carried out under a shielding gas atmosphere.

5. The method for producing a component from MAX phases as claimed in claim 1, wherein the scanning speed between the energy beam of the laser or electron beam and substrate with powder lies between 1000 mm/s and 1500 mm/s.

6. The method for producing a component from MAX phases as claimed in claim 1, wherein the power output is between 100 W and 170 W.