CN1052271A

CN1052271A - Two step vacuum smelting method for composite metal anti-abrasive hammer sheet and cutting knife

Info

Publication number: CN1052271A
Application number: CN 90109909
Authority: CN
Inventors: 吴仲行
Original assignee: New Type Material Tech Co Beijing Stone Group Co
Current assignee: New Type Material Tech Co Beijing Stone Group Co
Priority date: 1990-12-14
Filing date: 1990-12-14
Publication date: 1991-06-19

Abstract

The present invention makes antifriction metal (AFM) spare with two step vacuum smelting method with composition metal.The main cutting knife that is used as the hammer leaf of various beater grinders and in industry such as papermaking, plastics, rubber and pellet, is used as cutter, shredding machine or comminutor.The working position that it is characterized in that the steel substrate, as four jiaos or the sword limit of cutting knife of hammer leaf, the compound surperficial hardening agent bar of required hardness.The first step is prepared surperficial hardening agent bar with the fusion bonded forming method according to required size and hardness.Second step with the clinkering method for welding alloy bar securely metallurgical binding on the steel substrate and become composite metal anti-abrasive hammer sheet and cutting knife.

Description

Two step vacuum smelting method for composite metal anti-abrasive hammer sheet and cutting knife

The invention belongs to composition metal and make wearing piece.Mainly be applicable to the hammer leaf and the cutting knife of the work mechanisms such as comminutor of beater grinder, cutter, shredding machine.

Beater grinder is widely used in industrial production such as feed, starch, alcohol, coal dust, talcum powder.Hammer leaf is the main consumable accessory of beater grinder.The hammer leaf of present domestic use mainly contains two kinds, all belongs to the low gear hammer leaf, and a kind of is the heat treatment hammer leaf, and after quenching heat treatment, hardness reaches about HRc55 as the 65Mn hammer leaf.Another kind is the built-up welding hammer leaf, i.e. built-up welding WC on the clavicorn of steel substrate, and hardness can reach about HRc60.As for the hammer leaf described in the CN1043455A patent, be a kind of tentative hammer leaf, fail so far to put into serial production.The industry of saggar method vacuum sintering has three big difficult points to fail to reach a standard technically: the volume of first saggar itself is greater than hammer leaf, saggar about 3/4ths of the vacuum sintering stove burner hearth dischargeable capacity that will account for when shove charge, have only the combustion space about 1/4th can adorn hammer leaf, single furnace output is very low; It two is poor thermal conductivity of ceramic saggar, when saggar and saggar are layering clinkering, completely is raised to set fusion bonded temperature for making whole saggars, must be through the very long clinkering time; A basic principle of vacuum sintering technology is necessary Fast Heating, cooling fast, otherwise the steel substrate will lose original mechanical strength and rupture in use thereafter in long high-temperature heating process; It three is high-purity Al ₂O ₃Or ceramic saggar such as BN costs an arm and a leg, and the ceramic saggar of fragility is easy to crackedly in operating process and the clinkering process with fast cooling of being rapidly heated, and causes the production cost of hammer leaf too high.Finally fail to be applied to the production of hammer leaf in view of above reason saggar method vacuum sintering technology.

The hardness of U.S. Magnum built-up welding hammer leaf is about HRc69, and serviceability is better, but costs an arm and a leg, about 80 yuan of every agreement that contracts a film or TV play to an actor or actress RMB, and every of the price of homemade hammer leaf has only about 7 yuan.

The present common employing high-speed steel of industrial cutting knife is made through quenching heat treatment, and cutting edge hardness is about HRc58, and service life is very short, if when quenching hardness further improves again, then whole cutting knife will become fragile and fracture easily.

The object of the present invention is to provide a kind of composite metal anti-abrasive hammer sheet and cutting knife, can improve and accurately control the hardness of hammer leaf clavicorn and cutting knife cutting edge, improve service life effectively.Adopt two step method vacuum sintering technology, the cancellation saggar reduces manufacturing cost greatly, improves the quality of products, and batch process smoothly can have high input.

Composite metal anti-abrasive hammer sheet of the present invention is composited by two parts with section.Among Fig. 1 and Fig. 21 is respectively the steel substrate of hammer leaf and cutting knife, and 2 is respectively the surperficial hardening agent bar of hammer leaf and cutting knife, and these two parts become the integral body of firm metallurgical binding with more low-melting brazing alloy through the clinkering soldering.The vacuum sintering technology that is begun one's study in nineteen fifty-nine by the inventor has multiple function, can the clinkering shaping, clinkering soldering, clinkering coating, clinkering sealing of hole and clinkering repairing etc.The present invention has used preceding two kinds of functions, i.e. clinkering profiled surface hardening agent bar at first, and then alloy bar clinkering soldering on substrate.With two kinds of alloy bar alloyed powders in the table 1, mix according to certain proportioning, the relation of proportioning and alloy bar hardness is shown in table 2 for example, add an amount of retinal binding agent during mixing, but be mixed into molding powder machine, in the rectangle pressing mold, be pressed into the base bar again, be placed in 200 ℃ of drying bakers oven dry after, be placed in the vacuum sintering stove and become surperficial hardening agent bar by following system clinkering:

Vacuum 1 * 10 ^-1～1 * 10 ^-2MmHg

1200～1300 ℃ of clinkering forming temperatures

5 minutes clinkering time

Before the clinkering soldering, greasy dirt and oxide skin that need are removed the steel substrate surface with the alkali pickling, any alloyed powder with in the retinal blending brazing alloy powder is mixed into rarer viscose glue, alloy bar is smeared a little viscose glue, and stick on the sword limit of the clavicorn of hammer leaf substrate or cutting knife substrate.In 200 ℃ of drying bakers, after the oven dry, promptly be stacked in and carry out soldering in the vacuum sintering stove.The flat porcelain bead that several thickness of placement are about 3mm between adjacent two hammer leaves or cutting knife when stacking separates, the following clinkering system of the general employing of clinkering soldering:

Vacuum 1 * 10 ^-1～1 * 10 ^-2MmHg

1000 ± 10 ℃ of clinkering brazing temperatures

20 minutes clinkering time

The relation of table 2 alloyed powder proportioning and alloy bar hardness

Numbering	Alloyed powder proportioning (%)		Alloy bar hardness HRc
				CR-1	CO-2
	1 2 3 4 5 6	78 81 82 83 84 85				22 19 18 17 16 15	65 67.3 69 69.3 69.6 70

Brazing layer is extremely thin, generally has only tens microns, forms very firm metallurgical binding after the clinkering soldering between alloy bar and the substrate, and alloy bar can not come off.Compound hammer leaf is finished product after the clinkering soldering, the difference of the weight between per two hammer leaves is less than 5 grams, so in use, make pulverizer have good dynamic balance and can not shake or beat, be about 4 of built-up welding hammer leaf is accompanied the service life of composite metal anti-abrasive hammer sheet, is about 8 times of quenching hammer leaf.The cutting knife that clinkering is good also needs to put the first edge on a knife or a pair of scissors on grinding machine, and be more than 4 times of built-up welding cutting knife the service life of composite metal anti-abrasive cutting knife.

Embodiment:

The first step press in the table 2 No. 1 with No. 6 proportioning mixed C R-1 and CO-2 alloyed powder, add a little retinal and be mixed into the plasticity powder, in the rectangle pressing mold, be pressed into the base bar, after 200 ℃ of oven dry, be placed in the vacuum sintering stove, 1 * 10 ^-2MmHg, 1220 ℃ of following clinkerings 5 minutes promptly obtain hard alloy bar.

Second step added the viscose glue of NI-4 brazing alloy powder to above-mentioned alloy bar with retinal, sticked on the steel substrate that has cleaned up in advance, and after 200 ℃ of oven dry, the flat little porcelain bead thick with 3mm separates, and level overlays in the vacuum sintering stove, 1 * 10 ^-1MmHg, the anti-abrasive hammer sheet and the cutting knife of composition metal have promptly been made in 1000 ℃ of following clinkering solderings 20 minutes, and their material and dimensions are as shown in table 3;

In the accompanying drawing, Fig. 1 is the hammer leaf schematic diagram, and Fig. 2 is the cutting knife schematic diagram.

The material of table 3 embodiment hammer leaf and cutting knife and dimensions

Group	Title	Size		Material
						Substrate	Alloy bar	Substrate	Alloy bar hardness
		1 2 3 4	Hammer leaf hammer leaf hammer leaf cutting knife	180×50×5 178×50×6 226×49×6 155×90×6	30×5×2 30×6×2 40×6×2 155×6×2					No. 45 steel of No. 45 steel 65Mn of No. 45 steel	HRc65 HRc70 HRc65 HRc70

Claims

1, a kind of composite metal anti-abrasive hammer sheet and cutting knife.It is characterized in that hammer leaf and cutting knife all are composited by steel substrate and surperficial hardening agent bar two parts.

2, a kind of two step method vacuum sintering new technology of making composite metal anti-abrasive hammer sheet and cutting knife.It is characterized in that first step clinkering shaping alloy bar, second step became an integral body to alloy bar with steel substrate clinkering soldering.

3, according to described composite metal anti-abrasive hammer sheet of claim 1 and cutting knife, it is characterized in that alloy bar is made up of chromium base surface hard alloy and cobalt-based surface hardening agent, its clinkering forming temperature is about 1200 ℃.

4, according to described composite metal anti-abrasive hammer sheet of claim 1 and cutting knife, the percentage composition scope that it is characterized in that chromium base surface hard alloy in alloy bar is 78～85%, and the percentage composition scope of cobalt-based surface hardening agent is 15～22%.

5, according to the described two step method vacuum sintering of claim 2 new technology, it is characterized in that adopting a kind of low-melting Co-base or Ni-base surface hard alloy as brazing alloy, its clinkering brazing temperature is about 1000 ℃.