CN105543529A - Magnesium alloy composite refining method - Google Patents

Abstract

The invention provides a magnesium alloy composite refining method and belongs to the technical field of refining technologies. By means of the magnesium alloy composite refining method, gas shielding, solvent protecting, gas refining and solvent refining are combined, and the defects that the operation difficulty of a 'lower portion solvent method' is large, the refining labor intensity is high, the refining effect is unstable, solvent slag inclusions are liable to produce, and degassing cannot be conducted are overcome. A two-stage refining mode is put forward, that is, the refining process is conducted by being divided into two stages, the refining depth, the refining time, the gas flow and the solvent flow which are adopted in the two stages are all different; accordingly, the refining quality is improved, and the refining cost is reduced.

Description

A kind of magnesium alloy composite refining method

Technical field

The invention belongs to refining and modifying technical field, particularly relate to a kind of magnesium alloy composite refining method.

Background technology

Due to magnesium alloy easy firing, oxidizable, need carry out refining treatment, existing alloy refining equipment and method of refining cannot be applicable to magnesium alloy refining.What current magnesium alloy refining adopted is " bottom solvent method ", adopting stirring spoon to carry out dragging for end stirring refining needs operator to have higher operating skill, labour intensity is very large, refining effect affects very large by operator, the poor stability stirred, the defect problems such as easy generation solvent, oxide slag inclusion, solution quality is difficult to be guaranteed.Meanwhile, the method for refining spoon refining is adopted also cannot to reach the effect of degasification.

Summary of the invention

For solving the problems of the technologies described above, the invention provides a kind of magnesium alloy composite refining method, solve current magnesium alloy method operation easier large, refining labour intensity is high, refining effect is unstable, easy generation solvent slag inclusion, cannot the series of problems such as degasification be carried out, realize the composite refining of argon gas and solvent.

The present invention is achieved by the following technical programs.

A kind of magnesium alloy composite refining method provided by the invention, comprises the following steps:

1) by baking saturating magnesium alloy ingot enter stove fusing, put into crucible, after carrying out Metamorphism treatment at 720 ~ 780 DEG C, remove surperficial molten slag layer and evenly spread lower one deck solvent insulation leave standstill;

2) wash in the airway of oven dry insertion carnallitite solution, the argon flow amount of reconciling airway is 1.2L/min ~ 2.5L/min, then tilts to be inserted into by airway apart from crucible bottom 50 ~ 500mm depth;

3) open solvent quantitative supply device, make the quantity of solvent on crucible top layer keep constant, regulate the given speed of solvent to be 120g/min ~ 160g/min, refining 6min ~ 10min;

4) airway is up carried 10 ~ 500mm in the vertical direction, regulating argon flow amount to be 0.01 ~ 5L/min and solvent delivery rate is 10 ~ 1000g/min, then refining 2min ~ 6min;

5) after reaching refining time, take out airway, remove surperficial molten slag layer and evenly spread lower one deck solvent, be adjusted to 760 ~ 820 DEG C and leave standstill, time of repose >=15min, then pours into a mould; The sample of cast is tested.

Further, described solvent is RJ-2 solvent or RJ-5 solvent.

Principle of work of the present invention is:

(1) dry argon gas, by the dispersion apertures at airway mouth of pipe place, forms intensive argon gas small bubbles, emerges at 2/3 depth of magnesium liquid, and bubble divides with molten metal filing and contacts in uphill process.Because partial pressure of ar gas is higher, the hydrogen in metal constantly can enter bubble, after bubble emersion, and the benefit thereupon of the hydrogen in bubble, thus reach the object of dehydrogenation.Bubble can also adsorb less inclusion in uphill process, and floats with it and get rid of, and plays certain slagging-off effect.Meanwhile, the argon gas of emersion floats over superjacent because density ratio air is large, can play certain gas shield effect.

(2) rising of intensive bubble can also drive magnesium liquid to produce strong circulative convection up and down in the vertical direction; constantly solvent is spread equably on magnesium liquid surface; solvent fully can contact with magnesium liquid along with the liquid stream stirred up and down; effectively prevent magnesium liquid from burning; and the inclusion be suspended in magnesium liquid is captured, sunk to the bottom, thus realize the dual effect of solvent refined and solvent protection method.

(3) refining point two-stage is carried out, and the first step adopts the larger refining degree of depth and comparatively atmospheric flow, melt is stirred fiercer, to ensure in crucible that melt fully and solvent contacts.The second stage adopts the relatively little refining degree of depth and gas flow, while guaranteeing that melt continues to obtain refining, the slag formed in advance can sink to the bottom, and prevents the slag formed in advance from continuing to stir and contaminated melt with melt, thus improve refining qualities further, reduce refining cost.

Beneficial effect of the present invention is: adopt the combination that present invention achieves gas shield and solvent protection method, gas refinement and solvent refined.Compensate for " bottom solvent method " operation easier large, refining labour intensity is high, and refining effect is unstable, easily produces solvent slag inclusion, cannot carry out the defects such as degasification.The present invention proposes twin-stage refining pattern, namely carries out in refining process point two-stage, and the refining degree of depth that two-stage adopts, refining time, gas flow and solvent flux are all different, improve refining qualities, reduce refining cost.

Accompanying drawing explanation

Fig. 1 is the structural representation of the embodiment of the present invention.

In figure: 1-argon supply system valve, 2-under meter, 3-soft air-guide pipe, 4-airway, 5-solvent quantitative supply device.

Embodiment

Further describe technical scheme of the present invention below, but described in claimed scope is not limited to.

Embodiment one

Present embodiments provide a kind of magnesium alloy ZM5 alloy and meet method of refining; The device of the method by reference to the accompanying drawings shown in 1 carries out, specific as follows:

1) the saturating ZM5 alloy pig of baking is entered stove fusing, put into crucible (figure does not mark), after carrying out Metamorphism treatment at 720 DEG C ~ 740 DEG C, employing skimming ladle is removed surperficial molten slag layer and is evenly spread No. 2 solvents insulations of lower one deck and leaves standstill.

2) wash in airway (4) outlet side of drying insertion carnallitite solution, then the airway (4) after washing is connected with soft air-guide pipe (3).

3) first open argon supply system valve (1), then adjust flux meter (2) to argon flow amount is 1.2L/min ~ 1.6L/min.Airway is tilted to be inserted into apart from crucible bottom 150 ~ 200mm depth.

4) open solvent quantitative supply device (5), make the quantity of solvent on crucible top layer keep constant, regulate the given speed of solvent to be 120g/min ~ 160g/min, refining 6min ~ 8min.

5) airway is up carried 50 ~ 100mm in the vertical direction, regulating argon flow amount to be 0.8L/min ~ 1.2L/min and solvent delivery rate is 100g/min ~ 120g/min, then refining 2min ~ 4min.

6) after reaching refining time, take out airway, close solvent quantitative supply device, and then close argon supply system valve and under meter regulated valve.

7) airway is separated with soft air-guide pipe, then airway is put into carnallitite washing composition and wash 2min ~ 5min, be placed in stoving oven for subsequent use.

8) adopt skimming ladle remove surperficial molten slag layer and evenly spread lower one deck No. 2 solvents, be adjusted to 780 DEG C ~ 800 DEG C and leave standstill, time of repose >=15min, then pours into a mould.The sample of cast is tested.

Utilize the ZM5 alloy purification effect of method of refining process of the present invention compared with ordinary method, hydrogen richness is reduced to 8.1ml/100g by the 25.2ml/100g of ordinary method, and outgassing rate about reaches 67.9%; Tensile strength, unit elongation are compared and are improved about 19% and 24% respectively.

In above-mentioned, the solvent of use is RJ-2 solvent.

Embodiment two

Present embodiments provide a kind of magnesium alloy ZM6 alloy and meet method of refining; The device of the method by reference to the accompanying drawings shown in 1 carries out, specific as follows:

1) the saturating ZM6 alloy pig of baking is entered stove fusing, put into crucible, adopt skimming ladle to remove surperficial molten slag layer evenly spread lower one deck solvent, and adjust the temperature to 740 DEG C ~ 760 DEG C and leave standstill.

2) wash in airway (4) outlet side of drying insertion carnallitite solution, then the airway (4) after washing is connected with soft air-guide pipe (3).

3) first open argon supply system valve (1), then adjust flux meter (2) to flow is 2.0L/min ~ 2.5L/min.Airway is tilted to be inserted into apart from crucible bottom 150 ~ 200mm depth.

4) open solvent quantitative supply device (5), make the quantity of solvent on crucible top layer keep constant, regulate the given speed of solvent to be 150g/min ~ 200g/min, refining 8min ~ 10min.

5) airway is up carried 50 ~ 100mm in the vertical direction, regulate argon flow amount to be 1.2L/min ~ 1.5L/min and solvent delivery rate 120g/min ~ 150g/min, then refining 4min ~ 6min.

6) after reaching refining time, take out airway, close quantitative supply device, and then close argon supply system valve and under meter regulated valve.

7) airway is separated with soft air-guide pipe, then airway is put into carnallitite washing composition and wash 2min ~ 5min, be placed in stoving oven for subsequent use.

8) adopt skimming ladle remove surperficial molten slag layer and evenly spread lower one deck solvent, be adjusted to 780 DEG C ~ 810 DEG C and leave standstill, time of repose >=25min, then pours into a mould.

Utilize the ZM6 alloy purification effect of method of refining process of the present invention compared with ordinary method, hydrogen richness is reduced to 12.8ml/100g by the 32.7ml/100g of ordinary method, and outgassing rate about reaches 60.8%; Tensile strength, unit elongation are compared and are improved about 17% and 22% respectively.

In above-mentioned, the solvent of use is RJ-5 solvent.

Claims (2)

1. a magnesium alloy composite refining method, is characterized in that: comprise the following steps:

1) by baking saturating magnesium alloy ingot enter stove fusing, put into crucible, after carrying out Metamorphism treatment at 720 ~ 780 DEG C, remove surperficial molten slag layer and evenly spread lower one deck solvent insulation leave standstill;

2) wash in the airway of oven dry insertion carnallitite solution, the argon flow amount of reconciling airway is 1.2L/min ~ 2.5L/min, then tilts to be inserted into by airway apart from crucible bottom 50 ~ 500mm depth;

3) open solvent quantitative supply device, make the quantity of solvent on crucible top layer keep constant, regulate the given speed of solvent to be 120g/min ~ 160g/min, refining 6min ~ 10min;

4) airway is up carried 10 ~ 500mm in the vertical direction, regulating argon flow amount to be 0.01 ~ 5L/min and solvent delivery rate is 10 ~ 1000g/min, then refining 2min ~ 6min;

5) after reaching refining time, take out airway, remove surperficial molten slag layer and evenly spread lower one deck solvent, be adjusted to 760 ~ 820 DEG C and leave standstill, time of repose >=15min, then pours into a mould; The sample of cast is tested.

2. magnesium alloy composite refining method as claimed in claim 1, is characterized in that: described solvent is RJ-2 solvent or RJ-5 solvent.