High hardness amorphous composite and preparation method and application thereof

Abstract

The present invention relates to a high hardness amorphous composite, a method of preparing the high hardness amorphous composite and application thereof. The high hardness amorphous composite includes a basic alloy component, a hard additive and a bonding additive. The basic alloy component includes 45-60 mole % Zr, 5-10 mole % Hf, 5-15 mole % Al, 8-22 mole % Ni and 6-14 mole % Cu, the hard additive is ZrC or WC nanometer powder with addition amount at 12-26 wt % of the basic alloy component, particle diameter of the WC nanometer powder is 10-100 nm, and the bonding additive is any one or two selected from groups of Re, W or Mo with addition amount at 4-8 wt % of the basic alloy component. The high hardness Zr-based amorphous composite with good workability and formability is provided by improving composition of alloy based on ZrAlNiCu, adding new component and adjusting component content.

Claims

1. A high hardness amorphous composite, comprising: a basic alloy component, comprising 45-60 mole % Zr, 5-10 mole % Hf, 5-15 mole % Al, 8-22 mole % Ni and 6-14 mole % Cu; a hard additive being ZrC or WC nanometer powder with addition amount at 12-26 wt % of the basic alloy component, particle diameter of the ZrC or WC nanometer powder being 10-100 nm; and a bonding additive being any one or two selected from the group consisting of Re, W and Mo with addition amount at 4-8 wt % of the basic alloy component.

2. The high hardness amorphous composite according to claim 1, wherein the basic alloy component comprises 54-58 mole % Zr, 6-8 mole % Hf, 10-15 mole % Al, 15-20 mole % Ni and 8-12 mole % Cu.

3. The high hardness amorphous composite according to claim 1, wherein the hard additive is the ZrC nanometer powder with addition amount at 12-18 wt % of the basic alloy component.

4. The high hardness amorphous composite according to claim 1, wherein the bonding additive is Re with addition amount at 8 wt % of the basic alloy component.

5. The high hardness amorphous composite according to claim 1, further comprising B or Si with content at 0.5-2 wt % of the basic alloy component.

6. The high hardness amorphous composite according to claim 1, further comprising Nd with content at 0.5-2 wt % of the basic alloy component.

7. A method of preparing the high hardness amorphous composite according to claim 1, comprising: step a, weighing the basic alloy component, the hard additive and the bonding additive according to formulation ratio, mixing the hard additive and the bonding additive evenly to obtain a mixed raw material, then placing the mixed raw material on bottom of the basic alloy component to obtain a pending alloy raw material; step b, smelting the pending alloy raw material by means of electric arc smelting in an inert atmosphere of 0.01-0.05 MPa, and the smelting being conducted in a first process and a second process: the first process comprising controlling working current of electric arc in 10-50A and heating the pending alloy raw material until the pending alloy raw material melts into a liquid, the second process comprising increasing the working current of electric arc to 200-900A to mix the liquid of the pending alloy raw material evenly; and step c, molding and cooling the liquid of the pending alloy raw material at 10.sup.2-10.sup.3 K/s to obtain an amorphous composite ingot.

8. The method of preparing the high hardness amorphous composite according to claim 7, wherein the second process is repeated one or two times.

Description

DETAILED DESCRIPTION OF ILLUSTRATED EMBODIMENTS

(1) The present invention will be described with reference to the specific embodiments.

Embodiment 1-18

(2) Purity of the alloy raw materials is greater than 99.9%, and particle size of ZrC and WC nanometer powder is 10 nm. All the raw materials can be purchased from the market.

(3) Hardness of the amorphous alloy is characterized by Vickers hardness tested by Vickers hardness tester, test method is performed according to <<GB/T 7997-2014 Hard Alloy Vickers Hardness Test Method>>, and Hardness is characterized by HV10.

(4) The method of preparing a high hardness amorphous composite includes:

(5) step a, weighing the basic alloy component, the hard additive and the bonding additive according to formulation ratios in Table 1, mixing the hard additive and the bonding additive evenly to obtain a mixed raw material, then placing the mixed raw material on the bottom of the basic alloy component to obtain a pending alloy raw material;

(6) step b, smelting the pending alloy raw material by means of electric arc melting in an inert atmosphere of 0.01-0.05 MPa, and the smelting being conducted in a first process and a second process: the first process comprising controlling working current of the electric arc in 10-50 A and heating the pending alloy raw material until the pending alloy raw material melts into a liquid, the second process comprising increasing the working current of electric arc to 200-900 A to mix the liquid of the pending alloy raw material evenly; and

(7) step c, molding and cooling the liquid of the pending alloy raw material at 10.sup.2-10.sup.3 K/s to obtain an amorphous composite ingot. The amorphous composite ingot is molded by a conventional die-casting process or a conventional suction casting process, but not limited to it.

(8) Elemental composition and mole percent of the basic alloy component are shown in Table 1 below:

(9) TABLE-US-00001 TABLE 1 Embodiment No. Zr Hf Al Ni Cu 1 45 10 15 22 8 2 46 9 14 20 11 3 47 8 13 20 12 4 48 6 12 22 12 5 49 6 13 18 14 6 50 7 10 19 14 7 51 7 11 18 13 8 52 8 13 15 12 9 53 7 12 16 12 10 54 8 12 18 8 11 55 6 15 15 9 12 56 8 12 15 9 13 57 7 14 16 6 14 58 7 15 8 12 15 59 9 10 15 7 16 60 8 8 12 12 17 61 6 7 18 8 18 62 5 5 18 10

(10) According to the above table 1, ZrAlNiCuHf five-element alloy is prepared by conventional electric arc melting, and surface hardness of the five-element alloy without additives is tested.

(11) When the hard additive is ZrC or WC nanometer powder with content at 12 wt % of the basic alloy component, and the bonding additive is Re with content at 8 wt % of the basic alloy component, hardness test results are shown in Table 2 below:

(12) TABLE-US-00002 TABLE 2 ZrC WC No nanometer nanometer Additives powder + Re powder + Re Embodiment Hardness Hardness Hardness No. (Hv10) (HV10) (HV10) 1 554 655 658 2 557 649 661 3 548 663 674 4 569 674 675 5 547 666 675 6 555 654 662 7 588 652 648 8 567 663 660 9 568 662 657 10 569 659 659 11 574 671 670 12 584 669 668 13 576 675 674 14 586 678 679 15 577 665 668 16 568 654 668 17 557 675 674 18 568 668 671

(13) In embodiments 1-18, the amorphous composites obtained have a forming ability of equal or greater than 10 cm and a maximum forming ability of up to 22 cm. Hardness test results show that hardness and forming ability of the amorphous composite added with hard additive and bonding additive are greatly improved compared to those of the five-element alloy without additives.

Embodiment 19-32

(14) Composition of the basic alloy component and the preparation method are the same as that of embodiment 14. Hardness test results of the amorphous composite with the different hard additive and bonding additive are shown in the Table 3 below (value is percentage of additives mass to the basic alloy component mass):

(15) TABLE-US-00003 TABLE 3 Hardness Embodiment Hard Value No. additive Bonding additive (HV10) 19 14% ZrC 4% Re + 4% Mo 685 20 16% ZrC 4% Re + 2% Mo + 2% W 671 21 18% ZrC 8% Re 667 22 20% ZrC 8% Mo 663 23 22% ZrC 8% W 652 24 24% ZrC 8% Re 641 25 26% ZrC 8% Re 628 26 14% WC 4% Re + 4% Mo 683 27 16% WC 4% Re + 2% Mo + 2% W 671 28 18% WC 8% Re 662 29 20% WC 8% Mo 658 30 22% WC 8% W 644 31 24% WC 8% Re 643 32 26% WC 8% Re 619

(16) In embodiments 19-32, the amorphous composites obtained have a forming ability of equal or greater than 10 cm and a maximum forming ability of up to 22 cm. When content of hard additive nanometer powder is more than 22 wt % of the basic alloy component, hardness values of the amorphous composites decrease instead, and if the mass is over 26 wt %, no matter which kind of bonding additive is used, the amorphous composites obtained have surface cracking or bursting.

(17) The addition of various elements as the bonding additive is superior to the addition of a single element as the bonding additive. Re and Mo elements added are better than single W element added to the ability to form amorphous composites and the ability to fuse the hard additives.

Embodiments 33-46

(18) Composition of the basic alloy component and the preparation method are the same as those of embodiment 14. When the hard additive is ZrC nanometer powder with content at 12 wt % of the basic alloy component, the bonding additive is Re with content at 8 wt % of the basic alloy component, and B, Si or Nd also are added, the hardness test results are shown in the Table 4 below (Value is percentage of additive mass to the basic alloy component mass):

(19) TABLE-US-00004 TABLE 4 Hardness Embodiment Value No. Additives (HV10) 33 0.5% B 685 34 0.5% Si 687 35 1% B 689 36 1% Si 688 37 1.5% B 694 38 1.5% Si 692 39 2% B 699 40 2% Si 691 41 1% B + 0.5% Nd 691 42 1% Si + 0.5% Nd 695 43 1% B + 1% Nd 690 44 1% Si + 1% Nd 687 45 1% B + 2% Nd 684 46 1% Si + 2% Nd 685

(20) In embodiments 33-46, the addition of B and Si elements can further increase hardness of the amorphous composites, but no significant change occurs when the addition amount exceeds 2 wt %. The addition of appropriate amount of Nd element can enhance forming ability of the amorphous composites. However, forming ability of the amorphous alloys with only B or Si added does not distinct compared to the amorphous alloys without B or Si. After adding Nd, the amorphous composite is easier to form, and the forming ability can reach 22 cm.

(21) It should be noted that, current magnitude used in the smelting process of the amorphous composite is closely related to the alloy composition added, and when addition amount of the hard additive is large, the smelting current should be increased. When addition of the bonding additive or the addition of B, Si and Nd elements is performed, the arc smelting current should be higher.

(22) While the invention has been described in connection with what are presently considered to be the most practical and preferred embodiments, it is to be understood that the invention is not to be limited to the disclosed embodiments, but on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the invention.