CN101898228A

CN101898228A - Method for casting sound casting by using lost foam coated with high-performance coating in vibration way

Info

Publication number: CN101898228A
Application number: CN 201010241721
Authority: CN
Inventors: 刘玉满; 刘翔
Original assignee: Individual
Current assignee: Individual
Priority date: 2010-07-31
Filing date: 2010-07-31
Publication date: 2010-12-01

Abstract

The invention discloses a method for casting a sound casting by using a lost foam coated with a high-performance coating in a vibration way. The method is characterized in that: (1), the coating which is coated on the lost foam is the coating which has high strength, high tenacity, high crack resistance, and high air permeability at both normal temperature and high temperature; (2), during casting, vacuumization is performed, and when the negative pressure is stabilized in the range of between -0.06 and -0.04 MPa, a vibro-bench is started and casting is performed at the same; (3), after finishing casting and stopping vibrating, vacuum-pumping is continuously performed for 3 to 4 minutes. In the method, the cast is filled with the molten metal during casting under a 150Hz vibration condition, so the grains are refined during the solidification of the molten metal and a fine, pure and uniform network structure is formed on grain boundary. Test results show that the tensile strength of the sample of the iron and steel casting body can be improved by about 30 percent, the elongation can be improved by about 20 percent, and the compactness of the substrate can be improved by 6 to 8 percent.

Description

Method with high-performance coating lost foam casting vibration cast sound casting

Technical field

The present invention relates to lost foam casting, specifically is a kind of method with high-performance coating lost foam casting vibration cast sound casting.

Background technology

Lost foam casting is the history in more than 50 year, and over more than 50 year, the pouring procedure that lost foam casting is traditional is under static state to pour into a mould in dried sand negative-pressure condition lower mold.One of characteristics that lost foam casting is outstanding, be exactly under the dried sand negative-pressure condition, molten metal cooled and solidified speed is too slow, cause casting crystalline grain thick, organize not fine and closely, can not show a candle to the foundry goods that sand casting is produced in the tensile strength of foundry goods, percentage elongation, wear-resisting service life.This weak point has been brought great limitation to the lost foam casting industrial expansion, be used for the potassium steel under the wear-resisting wear-resistant working condition, ultra-high manganese steel, high, normal, basic wear-resisting alloy steel, important foundry goods such as antiwear cast iron alloy, not fine and close, a short-life international difficult problem, become first-class puzzlement in the domestic and international in recent ten years lost foam casting field, in addition, even the foundry goods that sand casting is produced, the crystal grain of scope that also only is several mm depths in foundry goods top layer is thinner, its elementary organization is fine and close a little, and still crystal grain is thicker and loose the deep layer of foundry goods and centre, and this is general present situation of domestic and international Foundry Production and problem.

Summary of the invention

The objective of the invention is to provide a kind of method with high-performance coating lost foam casting vibration cast sound casting.This method is because Foam Pattern face coat tensile strength is big, can pour into a mould under vibration condition, can make it in the process of setting grain refinement, gas is fully got rid of, and field trash fragmentation and disperse between its crystal boundary are evenly distributed, thereby strengthened the foundry goods mechanical performance comprehensively.

The present invention strengthens the method for foundry goods with high-performance coating lost foam casting vibration cast densification, comprise that the EPS bubble of foundry goods is smeared preparation, apperance brushing paint and the dry paint layer of apperance, sandbox is filled dry sand jolt ramming, moulding, plastic sheeting sealing sandbox casting mold, vacuumized negative pressure, casting, it is characterized in that:

1, employing all has the coating brushing apperance of high strength, high tenacity, high cracking resistance, highly-breathable under normal temperature and hot conditions;

2, the cast pattern behind the dry paint layer places sandbox to fill dry sand, and jolt ramming, and seal whole casting mold with plastic sheeting vacuumizes afterwards, when negative regulation-0.04～-during 0.06Mpa, Vibration on Start-up platform, limit vibration, limit cast;

3, cast finishes, and after stopping to vibrate, continues to vacuumize 3～4 minutes.

The coating of described high strength, high tenacity, high cracking resistance, highly-breathable is No. 6 powdery water based paints in Guilin that the commercially available Central-South casting smelting in Guilin City Materials Research Laboratories is produced, adding water mixes well, its materials consumption weight ratio is 1: 1.2, this coating is coated in the Foam Pattern surface, dry under 50～55 ℃, thickness is 1.5～2mm after the coating drying.

Through sampling Detection, its room temperature tensile strength 〉=1.40Mpa of dope layer, cavity shell tensile strength 〉=1.3Mpa behind 1000 ℃ of following roasting 30min, the cavity shell vibrates 10 minutes in the dried sand negative-pressure casting mold, frequency 150HZ, amplitude 0.5mm, the coating shell is excellent, is suitable for vibrating casting fully.

Described vibration, vibration frequency 150HZ, amplitude 0.5mm;

Advantage of the present invention is: the present invention is that molten metal is poured into a mould under vibration condition and is full of casting mold, the vibration field energy makes molten metal in the process of setting grain refinement, gas can fully overflow, molten metal viscosity descends and flowability and fillibility raising, field trash on the crystal boundary is broken and emersion liquid level or disperse evenly distribute, thereby foundry goods dense structure, mechanical performance is able to comprehensive reinforcement.The low-alloy bainite steel casting sampling Detection of the present invention through being 826KG to 1266 weight shows: after adopting the technology of the present invention, foundry goods tensile strength on average improves 35.6%, and percentage elongation on average improves 21.5%, and density on average improves 6.8%; Through adopting 812 sampling Detection of high manganese steel lining plate of the technology of the present invention, density on average improves 7.6% in addition.

Description of drawings

Fig. 1 is a lost foam casting negative pressure vibrating casting apparatus structure schematic diagram.

Among the figure: 1. Foam Pattern 2. coating shells 3. sandboxes 4. of foundry goods are filled dry sands 5. shake tables 6. sealing plastic films 7. pumped vacuum systems 8. mesh 9. cups of bleeding

The specific embodiment

Consult Fig. 1, a kind of fine and close method of strengthening foundry goods of lost foam casting vibration cast that adopts high-performance coating is carried out in existing lost foam casting negative pressure vibrating casting device, and its pouring procedure may further comprise the steps:

1, the Foam Pattern 1 of preparation foundry goods;

2, on Foam Pattern 1, be coated with to form coating shell 2, under 55 ℃ of temperature, dry, oven dry back thickness 1.5～2mm by No. 6 coating in the aforementioned Guilin for preparing;

3, the apperance that coating shell 2 is being protected places the sandbox 3 of steel plate structure;

4, fill dry sand 4;

5, Vibration on Start-up platform 5 consolidation dry sands;

6, with the whole casting mold of plastic sheeting 6 sealings;

7, start pumped vacuum systems 7, when negative regulation-0.04～-during 0.06Mpa, Vibration on Start-up platform 5, vibration frequency 150HZ, amplitude 0.5 ± 0.1mm, time of vibration 30～40s;

8, the gas in the casting mold enters pumped vacuum systems from the mesh 8 of bleeding and effluxes;

9, from cup 9 casting of molten metal (promptly under the dried sand negative-pressure condition, while vibrating cast), after finishing, cast treats that metal stops vibration when also solidifying substantially, and the pumped vacuum systems 3～4min that works on, with the heat in the diffusion casting mold.

Claims

1. method with high-performance coating lost foam casting vibration cast sound casting, comprise that the foundry goods bubble is smeared preparation, apperance brushing paint and the dry coating of apperance, sandbox is filled dry sand jolt ramming, moulding, plastic sheeting sealing sandbox casting mold, vacuumized and implement negative pressure, casting, it is characterized in that:

(1) coating of Foam Pattern brushing is for all having the coating of high strength, high tenacity, high cracking resistance, highly-breathable under normal temperature and hot conditions;

(2) cast the time vacuumizes, when negative regulation-0.04～-during 0.06Mpa, Vibration on Start-up platform, limit vibration, limit cast;

(3) pour stop the vibration after, continued to vacuumize 3～4 minutes.

2. method according to claim 1 is characterized in that: described coating with high strength, high tenacity, high cracking resistance, highly-breathable is that the water modulation that No. 6 powdery water based paints in Guilin add 1.2 times of weight portions forms.

3. method according to claim 1 is characterized in that: described on apperance the coating layer thickness of brushing paint be 1.5～2.0mm, coating is dried under 50～55 ℃ temperature.

4. method according to claim 1 is characterized in that: the described vibration frequency of step (2) is 150HZ, and amplitude is 0.5 ± 0.1mm.