CN105369104B - Al2O3‑ZrO2/ Co Ni BN cermet mold materials and preparation method thereof - Google Patents

Abstract

The Al ₂ O ₃ -ZrO ₂ /Co-Ni-BN cermet mold material and its preparation method relate to a non-ferrous alloy mold material and its preparation method. The material components include a matrix material and a toughening phase, and the matrix material is Al ₂ O ₃ , the particle size is 60nm, the mass percentage content is 72.25%-82.45%, the phase transformation toughening phase ZrO ₂ is 12.8%-14.6%, and the particle size is 200nm; the layered toughening phase BN is 1 %‑5%, the particle size is 100nm; the ductile toughening phase Co‑Ni is 2%‑10%, and the particle size is 100nm. Preparation process steps: the first step is the mixing and drying of raw materials, and the second part is powder molding and sintering. The prepared cermet mold material has a flexural strength of 1014-1423MPa, a fracture toughness of 7-14.7MPa.m ^1/2 and a hardness of 8.7-13.4GPa. The material is widely used as a wear-resistant extrusion die for thermal processing of non-ferrous metals.

Description

Al2O3-ZrO2 /Co-Ni-BN Cermet Mold Material and Its Preparation Method

technical field

The invention relates to a non-ferrous alloy mold material and a preparation method thereof, in particular to an Al ₂ O ₃ -ZrO ₂ /Co-Ni-BN cermet mold material and a preparation method thereof.

Background technique

With the rapid development of the material industry, molds have become irreplaceable equipment in the development of modern industry, laying the foundation for large-scale development of industry. Oxidation, mucous, corrosion and even welding often occur in the working environment of the mold, and traditional materials such as high-hard steel, cemented carbide, and traditional ceramics can no longer meet the actual production needs of the industry. Most of the commonly used ceramic mold materials in the industrial field are TZP/Al ₂ O ₃ , PSZ, Si ₃ N ₄ , Sialon, 3Y-TZP/Al ₂ O ₃ , Al ₂ O ₃ /Ni, etc. Due to the large difference in performance, the mold materials of different ceramic systems are limited by the use environment.

As a multi-phase composite cermet, it has excellent properties such as high temperature resistance, wear resistance, oxidation resistance, and thermal shock resistance. Its cermet mold has become a substitute for hard alloy and mold in the field of hot extrusion processing such as copper alloy, aluminum alloy, and titanium alloy. The best material for steel and ceramic moulds.

Contents of the invention

The purpose of the present invention is to provide an Al ₂ O ₃ -ZrO ₂ /Co-Ni-BN cermet mold material and its preparation method. The present invention prepares a high-performance cermet mold material, which can be better used in Harsh conditions such as wear, corrosion, high temperature, and high pressure have made significant progress in reducing processing costs and improving production efficiency in production.

The purpose of the present invention is achieved through the following technical solutions:

Al ₂ O ₃ -ZrO ₂ /Co-Ni-BN cermet mold material, the ingredients of the material include raw materials Al ₂ O ₃ powder, ZrO ₂ powder, BN, Co, Ni powder in equal proportions, Al ₂ O ₃ The content of nanoparticles is 72.25-82.45% by mass percentage, the content of ZrO ₂ micron particles is 12.75-14.55% by mass percentage, BN, Co, Ni are weighed according to the mass ratio 1:1:1, and the content is 3- 15%; the bending strength of the material is 1014~1423Mpa, the fracture toughness is 7-14.7MPa.m ^1/2 , and the hardness reaches 8.7-13.4Gpa.

Al ₂ O ₃ -ZrO ₂ /Co-Ni-BN cermet mold material preparation method, the method adopts the following process steps in one operation:

① Ingredients: Al ₂ O ₃ powder, ZrO ₂ powder, BN, Co, Ni powder in equal proportions are used as raw materials, the content of Al ₂ O ₃ nanoparticles is 72.25-82.45% by mass percentage, and the content of ZrO ₂ micron particles The content is 12.75-14.55% by mass percentage, BN, Co, Ni are weighed according to the mass ratio 1:1:1, and the content is 3-15% by total mass percentage;

② Ball mill mixing, put the prepared material into the ball mill, ball mill for 24 hours, put it in a drying oven, and dry at 60°C for 24 hours to prepare Al ₂ O ₃ -ZrO ₂ /Co-Ni-BN composite powder;

③ Powder molding and sintering: Add the composite powder processed in step ② into the graphite mold of the vacuum hot-pressing sintering furnace. ^-2, hot pressing for 30 minutes.

In the preparation method of the Al ₂ O ₃ -ZrO ₂ /Co-Ni-BN cermet mold material, in the step ②, the ball milling medium is selected from absolute ethanol, the balls are high-purity alumina balls, and the mixed composite powder The body was dried in a drying oven.

In the preparation method of the Al ₂ O ₃ -ZrO ₂ /Co-Ni-BN cermet mold material, the method step ③ is sintered by vacuum hot pressing sintering, the sintering temperature is 1450°C~1650°C, and the pressure is 30Mpa, vacuum degree 6×10 ^-2 , hot pressing for 30 minutes.

Advantage and effect of the present invention are:

The performance parameters of the Al ₂ O ₃ -ZrO ₂ /Co-Ni-BN cermet mold material of the present invention are: bending strength 1014-1423MPa, fracture toughness 7-14.7MPa.m ^1/2 , hardness 8.7-13.4Pa . When the Co-Ni-BN content is 4%, the flexural strength, fracture toughness and hardness of the sample reach the maximum value. The method of the invention prepares a high-performance cermet mold material, which can be better used in harsh conditions such as easy to wear, easy to corrode, high temperature, and high pressure, and has significant progress in reducing processing costs in production and improving production efficiency.

Description of drawings

Fig. 1 is the backscattering point image of the first node on the surface of the cermet;

Fig. 2 is the energy spectrum analysis collection of Fig. 1;

Fig. 3 is the sub-image of the backscattered points of the second node on the surface of the cermet;

Fig. 4 is the energy spectrum analysis collection of Fig. 3;

Figure 5 shows the fracture morphology of the sample after the BN-Co-Ni alloy content is 3% at 1500 ° C and 30 PMPa pressure for 30 min;

Figure 6 shows the fracture morphology of the sample after the BN-Co-Ni alloy content is 6% at 1500 ° C and 30 PMPa pressure for 30 min;

Figure 7 shows the fracture morphology of the sample after the BN-Co-Ni alloy content is 9% at 1500 ° C and 30 PMPa pressure for 30 min;

Figure 8 shows the fracture morphology of the sample after holding for 30 minutes at 1500 ° C and 30 PMPa pressure when the BN-Co-Ni alloy content is 12%;

Figure 9 shows the fracture morphology of the sample after the BN-Co-Ni alloy content is 15% at 1500 ° C and 30 PMPa pressure conditions for 30 min;

Fig. 10 is the flexural strength curve of sample;

Fig. 11 is the fracture toughness curve of sample;

Figure 12 is the hardness curve of the sample.

detailed description

The present invention will be described in detail below in conjunction with examples.

The material components of the present invention include a matrix material and a toughening phase, the matrix material is Al ₂ O ₃ , the particle size is 60nm, the mass percentage content is 72%-82%, and the phase transformation toughening phase ZrO ₂ is 12.8-14.6 mass fraction %, the particle size is 200nm; the layered toughening phase BN is 1%-5%, and the particle size is 100nm; the ductile toughening phase Co-Ni is 2%-10%, and the particle size is 100nm. Preparation process steps: the first step is the mixing and drying of raw materials, and the second part is powder molding and sintering. The prepared cermet mold material has a flexural strength of 1014-1423, MPa, a fracture toughness of 7-14.7MPa.m ^1/2 and a hardness of 8.7-13.4GPa.

The preparation process of the Al ₂ O ₃ -ZrO ₂ /Co-Ni-BN cermet mold material of the present invention adopts the following steps:

1) Ingredients: Al ₂ O ₃ powder, ZrO ₂ powder, BN powder, metal Co, Ni powder are used as raw materials, the content of Al ₂ O ₃ nanoparticles is 72-82% by mass percentage, and the mass fraction of ZrO ₂ is 12.8- 14.6%, BN, Co, Ni are weighed according to the mass ratio of 1:1:1, and the material content is 3-15% by mass percentage;

2) Ball mill mixing: put the prepared materials into a planetary ball mill, ball mill for 24 hours, put them in a vacuum drying oven, dry at 60°C for 24 hours, and ball mill to prepare Al ₂ O ₃ -ZrO ₂ /Co-Ni-BN composite Powder;

3) Powder molding and sintering: Add the composite powder processed in step 2 into a vacuum hot-pressing sintering furnace, under vacuum conditions, the temperature is 1450 ° C ~ 1650 ° C, the pressure is 30 MPa vacuum hot pressing for 30 minutes, and Al ₂ is prepared. O ₃ -ZrO ₂ /Co-Ni-BN cermet mold material.

Raw materials used in the present invention: Al ₂ O ₃ powder: particle size 60nm, purity Al ₂ O ₃ content >99.9%; ZrO ₂ powder: particle size 0.2 μm content >99.7%; BN particle size 0.1 μm, content >99.7%; Co powder and Ni powder: the particle size is 0.1 μm and the content is >99.9%.

Example 1

Using Al ₂ O ₃ nanoparticles, ZrO ₂ and BN, Co, Ni micro particles as raw materials, the content of Al ₂ O ₃ nanoparticles is 82.45% by mass percentage, the content of ZrO ₂ particles is 14.55% by mass percentage, equal mass The proportion of BN, Co, and Ni micron particle content is 1% respectively by mass percentage; then the prepared composite powder is added to the planetary ball mill, the ball milling medium is absolute ethanol, and high-purity alumina balls are used as balls, and ball milled for 24 hours, Then dry it in a drying oven for 24 hours to prepare Al ₂ O ₃ -ZrO ₂ /Co-Ni-BN composite powder. The composite powder is hot-pressed and sintered in a vacuum hot-pressing sintering furnace. The vacuum hot-pressing sintering temperature is 1550 ℃, the hot pressing pressure is 30 MPa, the hot pressing time is 30 min, and the vacuum degree is 6×10 ^-2 MPa, the Al ₂ O ₃ -ZrO ₂ /Co-Ni-BN cermet mold material is prepared. The bending strength of the material was detected by the unilateral three-point bending strength test; the fracture toughness of the material was detected by the SENB method; the Vickers hardness (Hv) of the material was measured by the Vickers indentation hardness method; the apparent hardness of the material was detected by scanning electron microscopy (SEM). Microstructure and fracture morphology.

The performance test results of the prepared Al ₂ O ₃ -ZrO ₂ /Co-Ni-BN cermet mold material are: the bending strength is 1014MPa, the fracture toughness is 7MPa.m ^1/2 , and the hardness reaches 8.7Gpa (fracture morphology See Figure 5).

Example 2

Using Al ₂ O ₃ nanoparticles, ZrO ₂ and BN, Co, Ni micro particles as raw materials, the content of Al ₂ O ₃ nanoparticles is 79.9% by mass percentage, the content of ZrO ₂ particles is 14.1% by mass percentage, equal mass The proportion of BN, Co, and Ni micron particle content is respectively 2% by mass percentage; then the prepared composite powder is added to the planetary ball mill, the ball milling medium is absolute ethanol, and high-purity alumina balls are used as balls for ball milling for 24 hours. Then dry it in a drying oven for 24 hours to prepare Al ₂ O ₃ -ZrO ₂ /Co-Ni-BN composite powder. The composite powder is hot-pressed and sintered in a vacuum hot-pressing sintering furnace. The vacuum hot-pressing sintering temperature is 1550 ℃, the hot pressing pressure is 30 MPa, the hot pressing time is 30 min, and the vacuum degree is 6×10 ^-2 MPa, the Al ₂ O ₃ -ZrO ₂ /Co-Ni-BN cermet mold material is prepared. The bending strength of the material was detected by the unilateral three-point bending strength test; the fracture toughness of the material was detected by the SENB method; the Vickers hardness (Hv) of the material was measured by the Vickers indentation hardness method; the apparent hardness of the material was detected by scanning electron microscopy (SEM). Microstructure and fracture morphology.

The performance test results of the prepared Al ₂ O ₃ -ZrO ₂ /Co-Ni-BN cermet mold material are: the bending strength is 1106MPa, the fracture toughness is 8.2MPa.m ^1/2 , and the hardness reaches 10.4Gpa (fracture shape See Figure 5).

Example 3

Using Al ₂ O ₃ nanoparticles, ZrO ₂ and BN, Co, Ni micro particles as raw materials, the content of Al ₂ O ₃ nanoparticles is 77.35% by mass percentage, the content of ZrO ₂ particles is 13.66% by mass percentage, equal mass The proportion of BN, Co, and Ni micron particle content is 3% respectively by mass percentage; then the prepared composite powder is added to the planetary ball mill, the ball milling medium is absolute ethanol, and high-purity alumina balls are used as balls, and ball milled for 24 hours, Then dry it in a drying oven for 24 hours to prepare Al ₂ O ₃ -ZrO ₂ /Co-Ni-BN composite powder. The composite powder is hot-pressed and sintered in a vacuum hot-pressing sintering furnace. The vacuum hot-pressing sintering temperature is 1550 ℃, the hot pressing pressure is 30 MPa, the hot pressing time is 30 min, and the vacuum degree is 6×10 ^-2 MPa, the Al ₂ O ₃ -ZrO ₂ /Co-Ni-BN cermet mold material is prepared. The bending strength of the material was detected by the unilateral three-point bending strength test; the fracture toughness of the material was detected by the SENB method; the Vickers hardness (Hv) of the material was measured by the Vickers indentation hardness method; the apparent hardness of the material was detected by scanning electron microscopy (SEM). Microstructure and fracture morphology.

The performance test results of the prepared Al ₂ O ₃ -ZrO ₂ /Co-Ni-BN cermet mold material are as follows: the bending strength is 1372MPa, the fracture toughness is 12.6MPa.m ^1/2 , and the hardness reaches 11.32Gpa (fracture shape See Figure 5).

Example 4

Using Al ₂ O ₃ nanoparticles, ZrO ₂ and BN, Co, Ni micro particles as raw materials, the content of Al ₂ O ₃ nanoparticles is 74.8% by mass percentage, the content of ZrO ₂ particles is 13.2% by mass percentage, equal mass The proportion of BN, Co, and Ni micron particle content is 4% by mass percentage; then the prepared composite powder is added to the planetary ball mill, the ball milling medium is absolute ethanol, and high-purity alumina balls are used as balls, and ball milled for 24 hours. Then dry it in a drying oven for 24 hours to prepare Al ₂ O ₃ -ZrO ₂ /Co-Ni-BN composite powder. The composite powder is hot-pressed and sintered in a vacuum hot-pressing sintering furnace. The vacuum hot-pressing sintering temperature is 1550 ℃, the hot pressing pressure is 30 MPa, the hot pressing time is 30 min, and the vacuum degree is 6×10 ^-2 MPa, the Al ₂ O ₃ -ZrO ₂ /Co-Ni-BN cermet mold material is prepared. The bending strength of the material was detected by the unilateral three-point bending strength test; the fracture toughness of the material was detected by the SENB method; the Vickers hardness (Hv) of the material was measured by the Vickers indentation hardness method; the apparent hardness of the material was detected by scanning electron microscopy (SEM). Microstructure and fracture morphology.

The performance test results of the prepared Al ₂ O ₃ -ZrO ₂ /Co-Ni-BN cermet mold material are: the bending strength is 1423MPa, the fracture toughness is 14.7MPa.m ^1/2 , and the hardness reaches 13.4Gpa (fracture shape See Figure 5).

Example 5

Using Al ₂ O ₃ nanoparticles, ZrO ₂ and BN, Co, Ni micro particles as raw materials, the content of Al ₂ O ₃ nanoparticles is 72.25% by mass percentage, the content of ZrO ₂ particles is 12.75% by mass percentage, equal mass The proportion of BN, Co, and Ni micron particle content is 5% by mass percentage; then add the prepared composite powder into the planetary ball mill, the ball milling medium is absolute ethanol, high-purity alumina balls are balls, and the ball mill is 24h. Then dry it in a drying oven for 24 hours to prepare Al ₂ O ₃ -ZrO ₂ /Co-Ni-BN composite powder. The composite powder is hot-pressed and sintered in a vacuum hot-pressing sintering furnace. The vacuum hot-pressing sintering temperature is 1550 ℃, the hot pressing pressure is 30 MPa, the hot pressing time is 30 min, and the vacuum degree is 6×10 ^-2 MPa, the Al ₂ O ₃ -ZrO ₂ /Co-Ni-BN cermet mold material is prepared. The bending strength of the material was detected by the unilateral three-point bending strength test; the fracture toughness of the material was detected by the SENB method; the Vickers hardness (Hv) of the material was measured by the Vickers indentation hardness method; the apparent hardness of the material was detected by scanning electron microscopy (SEM). Microstructure and fracture morphology.

The performance test results of the prepared Al ₂ O ₃ -ZrO ₂ /Co-Ni-BN cermet mold material are: the bending strength is 1408Mpa, the fracture toughness is 13.4MPa.m ^1/2 , and the hardness reaches 12.52Gpa (fracture shape See Figure 5).

Claims (1)

1. Al ₂ O ₃ -ZrO ₂ /Co-Ni-BN cermet mold material, characterized in that the ingredients of the material include raw materials Al ₂ O ₃ powder, ZrO ₂ powder, BN, Co, Ni in equal proportions Powder, the content of Al ₂ O ₃ nanoparticles is 72.25-82.45% by mass percentage, the content of ZrO ₂ micron particles is 12.75-14.55% by mass percentage, and the content of BN, Co, and Ni is weighed according to the mass ratio of 1:1:1 According to the total mass percentage of 3-15%, the bending strength of the material is 1014~1423MPa, the fracture toughness is 7-14.7MPa.m ^1/2 , and the hardness reaches 8.7-13.4GPa.