阅读说明：本技术 基于原位制造的合金的用碳化钨增强的复合材料及其生产方法 (Composite material reinforced with tungsten carbide based on an in-situ produced alloy and method for the production thereof ) 是由 埃娃·欧莱伊尼克 于 2019-04-30 设计创作，主要内容包括：本发明涉及一种基于原位生产的合金,尤其是铁基合金的用呈晶体和/或颗粒形式的碳化钨增强的复合材料,其特征可在于以下事实,复合层和/或复合区内的复合材料的微结构包括提供均匀宏观和微观分布的小面型晶体(6)和/或小面型颗粒碳化钨,其中所述碳化钨的晶体(6)和/或颗粒包括填充有基于金属的合金的不规则和/或圆形和/或卵形纳米和/或微米区域(7)。本发明还涉及用于生产所述复合材料的粉末组合物及其生产方法以及由这样的复合材料或使用所述方法制成的浇铸工作元件。(The invention relates to a composite material reinforced with tungsten carbide in the form of crystals and/or particles based on an in situ produced alloy, in particular an iron-based alloy, which may be characterized by the fact that the microstructure of the composite material within the composite layer and/or the composite zone comprises faceted crystals (6) and/or faceted particulate tungsten carbide providing a uniform macroscopic and microscopic distribution, wherein the crystals (6) and/or particles of tungsten carbide comprise irregular and/or circular and/or oval nano-and/or micro-areas (7) filled with a metal-based alloy. The invention also relates to a powder composition for producing said composite material, to a method for producing same, and to a cast working element made of such a composite material or using said method.)

1. Composite material reinforced with tungsten carbide in crystalline and/or particulate form based on an in situ produced alloy, in particular a cast iron based alloy, characterized in that the microstructure of the composite material within the composite layer and/or composite zone comprises facet-type crystals (6) and/or facet-type particles of tungsten carbide providing a homogeneous macroscopic and microscopic distribution, wherein said crystals (6) and/or particles of tungsten carbide comprise irregular and/or circular and/or oval nano-and/or micro-areas filled with a metal based alloy.

2. Composite material according to claim 1, characterized in that said irregular and/or ovoid and/or circular nano-and/or micro-zones (7) filled with metal-based alloy are located in the inner part of the crystals (6) and/or particles of tungsten carbide and in the outer part close to the wall, their structure is homogeneous (8), and said crystals (6) and/or particles are formed in situ within the liquid alloy and are present within a matrix formed after the crystallization process of said alloy.

3. Composite material according to claim 1 or 2, characterized in that the volume of at least one type of tungsten carbide is 15 to 90% by volume, preferably 25 to 75% by volume.

4. Composite material according to claim 1 or 2, characterized in that the size of the particles and/or crystals (10) of tungsten carbide is preferably between 0.5 and 30 μm.

5. Composite material according to claim 1 or 2, characterized in that, in the area of the crystals (6) of tungsten carbide, the size of the area filled with metal or alloy is 0.1 to 4.5 μm.

6. Composite material according to claim 1 or 2, characterized in that it comprises an additional type of carbide or boride other than SiC, in particular TiC, MoC, NbC, ZrC, VC, TaC, TaB, TiB, subjected to a self-propagating high-temperature synthesis reaction₂Or mixtures thereof.

7. Powder mixture for producing a composite material according to claims 1 to 5, characterized in that it comprises tungsten in the range of 90-97% wt. and carbon in the range of 3-10% wt. especially carbon in the form of high purity carbon or its high content of other supports or mixtures thereof, preferably tungsten in the range of 93-95% wt. and carbon in the range of 5-7% wt. preferably tungsten in an amount of about 94% wt. and carbon in the form of graphite in an amount of about 6% wt.

8. Powder mixture of a composite material comprising tungsten carbide in a composite layer or zone for producing a wear part according to claim 6, characterized in that it comprises:

a. tungsten powder, in particular in the form of microcrystalline powder or nanoparticulate agglomerates or other carriers with a high tungsten content,

b. carbon powder, especially in the form of graphite or other support with a high carbon content or mixtures thereof, and

c. in the form of a substrate for a carbon forming reactionOf a catalyst other than WC or boride which undergoes a self-propagating high-temperature synthesis reaction, in addition to SiC, in particular TiC, MoC, NbC, ZrC, VC, TaC, TaB, TiB₂Or mixtures thereof.

9. Method for producing a composite material according to any one of claims 1 to 6 in the form of a composite layer, comprising the following phases:

a) covering a mould cavity or mould core, in particular a sand core, with a liquid reactive cast coating (2) comprising the powder mixture of claim 7 or 8 and a carrier,

b) drying, in particular at a temperature equal to or higher than 100 ℃,

c) the mould cavity is cast with an alloy, in particular an iron-based alloy, wherein the heat supplied by the liquid alloy in the form of high temperature provides the energy required to initiate the in situ reaction of the ceramic phase in the form of at least one type of tungsten carbide or tungsten carbide with the addition of other types of carbides that undergo a self-propagating high temperature synthesis reaction and represent catalysts for the tungsten carbide synthesis reaction.

10. The method according to claim 9, characterized in that the carrier is a solution of a solvent added with a polymer, preferably the solvent is an alcohol, especially ethanol, and preferably the polymer is a resin with low gassing potential, especially rosin.

11. The method of claim 9, wherein the reactive cast coating has a surface density of 0.29 to 2g/cm²More preferably 0.29 to 0.6g/cm²Most preferably it is 0.5g/cm²。

12. Method according to claim 9, characterized in that the percentage ratio of the powder mixture to the carrier according to claim 7 or 8 is from 6:1 to 1:1, preferably 4: 1.

13. A method of producing a composite material according to any one of claims 1 to 6 in the form of a composite zone, comprising the steps of:

a) preparing a powder mixture according to claim 7 or 8;

b) compacting said powder mixture in the form of a cast compact, which may have different forms, in particular granules, compacts, preforms or compacts

c) Inserting at least one cast compact into the mold cavity using a mounting element,

d) the mould cavity is cast with an alloy, in particular an iron-based alloy, wherein the heat supplied by the liquid alloy in the form of high temperature provides the energy required to initiate the in situ reaction of the ceramic phase in the form of at least one type of tungsten carbide or tungsten carbide with the addition of other types of carbides that undergo a self-propagating high temperature synthesis reaction and represent catalysts for the tungsten carbide synthesis reaction.

14. Method according to claim 13, characterized in that the pressure of the reagent pressing is between 100 and 650MPa, preferably between 250 and 600MPa, most preferably between 460 and 550MPa, wherein especially when said pressure is obtained using a compaction method, especially using cold isostatic pressing, uniaxial or biaxial cold pressing.

15. Cast structural element comprising a composite material according to claims 1 to 6 or obtained according to claims 9 to 14.