CN1718314A - Containless continuous casting technological method of aluminium silicon bonding wire - Google Patents

Abstract

A conticasting technology without mould for the bonded Al-Si wire used for IC includes such steps as preparing the cast ingot of intermediate Si-Al alloy (A1-10-20%Si), adding it to the molten Al to obtain molten Al-(0.85-1.15%) Si alloy, and conticasting in non-mould mode by direct pulling-up and quick cooling.

Description

The no mould continuous casting process of aluminium silicon bonding line

Technical field: the invention belongs to the smelting and the processing of alloy material, it is specifically related to the no mould continuous casting process of aluminium silicon bonding line.

Background technology: bonding line is the main material of encapsulation in the encapsulation of integrated circuit, is the line of silicon chip and external frame.Bonding line has multiple material, and what Recent study and use were maximum is AL-1%SI alusil alloy bonding line, and it has the advantage that performance is good, cost is low.In making aluminium silicon bonding line process, obtaining column crystal blank wire rod is its necessary condition.Everybody is invented by the Japanese at the hot-mold continuous cast technology of generally acknowledging at present, its essence is the cold mould in the continuous casting is become the hot-cast type, avoids forming core on mould wall, has formed the unidirectional solidification condition, thereby has obtained the column crystal ingot casting of unidirectional solidification.Domesticly carried out extensively and profoundly research on this basis, but all do not break away from casting mold in its casting process, the bonding line AL-1%Si wire rod of being produced can really successfully be applied to actual production, yet there are no report.All adopt import bonding line AL-1%Si wire rod in the ultra-fine bonding aluminum steel of other manufacturer's trial-production high strength process, therefore solving the AL-1%SI wire rod is the key of development and production bonding line extra fine filament.

Summary of the invention: the objective of the invention is to overcome aforesaid technical barrier and be special this programme---the no mould continuous casting process of aluminium silicon bonding line that proposes of columanar structure's structure of obtaining bonding aluminum steel AI-1%Si wire rod, it has taked novel no mould continuous casting technology measure, can throw off casting mold, solution guarantees heat radiation longitudinally under condition of fast cooling, obtained columanar structure's bar of unidirectional array.

By as above design, the no mould continuous casting process of the aluminium silicon bonding line that this programme proposed is characterized in that the product of this no mould continuous casting has the structure of unidirectional column crystal, and its technical process is as follows:

1. prepare intermediate alloy: get fine aluminium 99.999%, monocrystalline silicon 99.999% is made AL-(10～20%) SI alloy cast ingot;

2. in the fine aluminium liquation of smelting furnace, add the intermediate alloy ingot casting and make AL-(0.85-1.15%) SI liquation, 720-780 ℃ of alloy one fusion temperature;

3. the liquation in the smelting furnace inserts drawing bar with nitrogen or argon shield from the continuous casting furnace side, draws melt, delivers to guide wheel, and its outlet temperature is 720-780 ℃;

4. cooling water flow 70-120L/H, coolant temperature 0-15 ℃;

5. pull out the hauling speed 500-1500mm/min of bar, the protective gas of casting process is nitrogen or argon gas.Static pressure face height 5-15mm.

Adopt this programme can embody following superiority: because this technology has been cancelled the crystallizer casting mold, utilize the surface tension of aluminium alloy, shortened solid-liquid two-phase section distance, improved the thermograde of solid-liquid interface greatly, rationally control the intensity of cooling of cooling medium in addition, guarantee heat radiation along the longitudinal direction, obtained columanar structure's bar of unidirectional array, the bar diameter is φ 5-φ 8mm, and it is to produce the required desirable blank of bonding aluminum steel extra fine filament.Each technological parameter rationally mates in the no mould casting process, can obtain best column crystal orientation, for follow-up hot candied process has been established the favorable tissue basis.

Description of drawings: Fig. 1 is the schematic diagram of the no mould continuous casting process of this programme aluminium silicon bonding line.

The specific embodiment: present technique is before preparation AL-(0.85-1.15) %Si alloy wire, prepare AL-(10%-20%) Si aluminium silicon intermediate alloy ingot casting earlier, in the fine aluminium liquation of smelting furnace, add the intermediate alloy ingot casting then, make AL-(0.85-1.15%) SI liquation, the alloying component of the finished product wire rod of this programme is AL+ (0.85-1.15%) Si, the purity 99.999% of AL wherein, all the other composition Fe, Cu, Mg, Mn equal size＜100ppm, Si is a monocrystalline silicon, purity 99.999%.This technology is utilized the surface tension of liquid aluminium silicon alloy according to aluminium silicon binary alloy phasor principle, draws the alloy of molten state on homemade horizontal continuous casting equipment with drawing bar, has realized the no mould continuous casting of bonding line AI-1%Si alloy wire.There is the mould continuous casting to compare with other AI-1%Si alloy, cancelled mold, made solid-liquid two-phase section in the casting process be as thin as a wafer end face, the thermograde of solid-liquid interface is enough big like this, avoided the forward position of freezing interface to produce constitutional supercooling or external core, the column crystal cross growth is restricted; By the intensity of cooling of strict control cooling water, guarantee heat radiation along the longitudinal direction in addition, obtained uniform unidirectional columanar structure bar.

Through engineer testing repeatedly, the optimal processing parameter of this programme is:

Intermediate alloy silicone content 10-20%;

720-780 ℃ of alloy one melting temperature;

720-780 ℃ of bar outlet temperature;

Cooling medium consumption 70-120L/H;

Coolant temperature 0-15 ℃;

Bar hauling speed 500-1500mm/min;

The protective gas of casting process is nitrogen or argon gas, static pressure face height 5-15mm.

Claims (1)

1. the no mould continuous casting process of an aluminium silicon bonding line is characterized in that the product of this no mould continuous casting has the structure of unidirectional column crystal, and its technical process is as follows:

1. prepare intermediate alloy: get fine aluminium 99.999%, monocrystalline silicon 99.999% is made AL-(10～20%) SI alloy cast ingot;

2. in the fine aluminium liquation of smelting furnace, add the intermediate alloy ingot casting, make AL-(0.85-1.15%) SI solution, 720-780 ℃ of alloy one fusion temperature;

3. the liquation in the smelting furnace inserts drawing bar with nitrogen or argon shield from the continuous casting furnace side, draws melt, delivers to guide wheel, and its outlet temperature is 720-780 ℃;

4. cooling water flow 70-120L/H, coolant temperature 0-15 ℃;

5. pull out the hauling speed 500-1500mm/min of bar, the protective gas of casting process is nitrogen or argon gas, static pressure face height 5-15mm.

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