CN2273422Y - Horizontal apparatus for testing electrical resistance of molten metal and alloy - Google Patents

Abstract

The utility model relates to an apparatus for measuring the electrical resistance of molten metals and alloys, which is characterized in that three stainless steel tubes with different diameters are welded into a combined container in the mode of a measuring tube-a homogenizing chamber-a connecting tube. When the container is vertically arranged in a crucible furnace and is heated with thermal insulation, the ingredient homogenization of a sample can be realized. When the container is horizontally arranged in a horizontal temperature control furnace, the electrical resistance of molten metals and alloys can be measured. The utility model has the advantages of simple structure, easy manufacturing, convenient use, and accurate measurement, and is especially suitable for measuring the electrical resistance of molten metals and alloys with relatively high melting points and for measuring the electrical resistance of different ingredient samples of the same alloy system.

Description

The electric resistance measuring apparatus of horizontally-arranged stainless steel molten metal and alloy

The utility model is the electric resistance measuring apparatus of a kind of horizontally-arranged stainless steel molten metal and alloy.It belongs to the technical field of measurement mechanism.

The resistance measurement of molten metal and alloy is far beyond the resistance measurement difficulty of normal temperature solid metallic and alloy.Because the former is in the condition of high temperature, prevent oxidation, and the shape of melt sample is unfixing.The electric resistance measuring apparatus of molten metal and alloy comprises the container of a vacuum-pumping and logical protective atmosphere.Draw four contact conductors in the container, be equipped with electric bridge and do the four probe method resistance measurement, enclose thermopair, container is placed heating furnace, can do to change the resistance measurement of temperature.Measuring vessel is as making of insulating materials such as glass or quartz glasss, and advantage is the measuring accuracy height, but and the usefulness of double as thermoelectrical potential measurement, shortcoming is that the measurement temperature can not be very high, and the glass container cracky.Measuring vessel can measure very high temperature as making of stainless-steel tube, and rustless steel container cracky not, and but, measured resistance is the parallel resistance of the melt sample in steel pipe and the pipe, so need measure sky steel pipe resistance in advance to deduct it.

In the technology of the existing measuring vessel of making molten metal resistance with stainless-steel tube, measuring tube is the stainless-steel tube of both ends open.During experiment, measuring tube is perpendicular to be put.Sample melts in being connected in the Sheng sample hose of measuring tube lower end.Vacuumize with the exhaust tube that is connected in the measuring tube upper end, from advancing tunger tube, sample is pressed into the measuring tube from containing sample hose again, just can carry out resistance measurement to containing the sample hose applying argon gas.Be close to the road and influence the four probe method measurement for the remainder that does not make this device forms electricity at the measuring tube two ends, except measuring tube is to make of stainless-steel tube, and four contact conductors that are welded on the measuring tube are outside the tinsel, and the remaining part of whole device (contain sample hose, exhaust tube, advance tunger tube and feed pipe) is all made with nonconducting quartz glass.Measuring tube and Sheng sample hose also have the connection between measuring tube and the exhaust tube all to adopt stainless steel---the quartz glass welding.R.Xu and the used device of W.Van dev Lugt can be used as the representative (seeing the 2389th page of the 156/158th the 740th page of the 1st phase of volume of Journa1 of Non-Crystalline Solids.1993 and the 4th the 9th phase of volume of Journal of Physics.Matter.1992) of prior art.

The shortcoming of prior art: the open two ends of stainless steel measuring tube all have other parts to link to each other, and for guaranteeing electrical isolation, other parts are all made with quartz glass.Quartz glass and stainless welding be difficulty very, and the quartz glass parts cracky.

The purpose of this utility model is: overcome the weakness of prior art, package unit all is welded with stainless-steel tube, cancellation stainless steel---quartz glass coupling part.Thereby simplified processing technology greatly, and install durable.

In order to realize that the technical measures that the utility model is taked are: the measuring tube that changes the both ends open of prior art is an end opening, the pipe of other end sealing, and what link to each other with measuring tube has only the homogenising chamber, and it only is connected in the openend of measuring tube.Because measuring tube can not form electric loop with other parts, just do not require that other parts are made of quartz glass to guarantee electrical isolation, so all available stainless steel manufacturing of package unit.For sample can be filled into the measuring tube of end sealing from the homogenising chamber, during measurement, we are horizontally-arranged with measuring tube.Under vacuum state, the melt sample can the gravity of dependence own flows into automatically from the homogenising chamber that is in the top and is full of measuring tube.In the homogenising chamber, add argon gas again, help sample is pressed into measuring tube.Whole measuring vessel is reduced to the connection container that is welded with three different stainless-steel tubes of diameter.Avoided stainless steel---the difficulty of quartz glass welding.

The utility model device as shown in drawings.Main body is welded by three sections different stainless-steel tubes of diameter.The sealing of one end of measuring tube (1), its internal diameter is generally 3 to 6mm, and length is 60 to 200mm, and tube wall is thinner, generally gets 0.3 to 1mm, so that the resistance of measuring tube itself is enough big.The measuring tube outside is welded with five nickel filaments and makes contact conductor (2), and wherein a and d are current feed, and b and c are voltage lead, make the usefulness of four probe method measuring resistance.Whether the sample that a contact conductor e of close measuring tube blind end melts when aiming at check measurement has been filled into the d point with position far away.If molten metal has flow to the de section, the resistance of the inevitable de section that records during less than blank pipe of the resistance of then measured de section.The open end of measuring tube is welded on the side of homogenising chamber (3) near an end place (claiming that this end is the top).When this was installed perpendicular putting, the homogenising chamber was made the fusing sample and is made the usefulness of sample composition homogenising.Therefore, the volume of homogenising chamber should be enough big, so that erect when putting, sample only is filled in and measures the following part of the mouth of pipe in the homogenising chamber.The volume of homogenising chamber is generally 5 to 60cm ³, at end face (or side) welding connecting pipe (4) on the top of homogenising chamber, its internal diameter is generally 5 to 10mm, and length is 400 to 1000mm.The other end of connecting pipe is connected in a stop,threeway (5) by a vacuum rubber pipe, is external to vacuum pump (6) and inert gas gas cylinder (7) by this piston.Unplug the vacuum rubber pipe, the fragment sample can be added to the homogenising chamber from connecting the mouth of pipe, the connecting pipe opening at top, homogenising chamber end face from measuring tube mouth of pipe position (or opening is in the position on side, homogenising chamber and measuring tube mouth of pipe opposite) farthest, so that it is horizontally-arranged at this device, and when making measuring tube be in extreme lower position, sample flows into and fills measuring tube, does not flow in the connecting pipe and goes and do not have sample.During experiment, extract the vacuum rubber pipe, raw material is joined the homogenising chamber from connecting the mouth of pipe.Connect the vacuum rubber pipe again, vacuumize, lead to argon gas, repeated multiple times is caught up with most remnant oxygen.Under argon shield, this device setting is placed crucible oven, heat tracing melts sample in the homogenising chamber, and homogenising.After vacuumizing, this device is moved into horizontal temperature control furnace from crucible oven.This device is being changed into when horizontally-arranged from perpendicular putting, should note making measuring tube to be in below,, avoiding it to flow into connecting pipe so that the melt sample flows into measuring tube automatically from the homogenising chamber.Applying argon gas is again avoided air to bleed and is caused the sample oxidation.In addition, the sample that the pressure of argon gas also can help to melt overcomes capillary action, flows to the measuring tube that is in vacuum state.Measure the resistance between de two lead-in wires this moment, find significantly to reduce when its value is measured than blank pipe, this shows that sample has been filled into the d point with far away.At middle deployment one thermopair (8) of measuring tube, insert a digital voltmeter (9) to measure temperature.Four contact conductors are connected electric bridge or potential difference meter (10) measuring resistance.With radiator valve or adjustable transformer control furnace temperature, just can measure the resistance at each temperature, measured resistance value is the stainless-steel tube between two voltage lead b and the c and the parallel resistance of sample.

Compared with the prior art, the utility model is simple in structure, and handling ease is easy to use.It is more convenient when particularly the series resistance that changes composition for same alloy system work is measured.

Description of drawings:

Accompanying drawing is the electric resistance measuring apparatus of horizontally-arranged stainless-steel tube molten metal and alloy.

1 is measuring tube in the accompanying drawing, 2 is contact conductor, and 3 is the homogenising chamber, and 4 is connecting pipe, solid line is the situation of the connecting pipe mouth of pipe when being connected on homogenising chamber end face, dotted line is the situation of the connecting pipe mouth of pipe when being connected on side, homogenising chamber, and 5 is stop,threeway, and 6 is vacuum pump, 7 is the inert gas gas cylinder, 8 is thermopair, and 9 is digital voltmeter, and 10 is electric bridge or potential difference meter.

In the accompanying drawing, 1 to 4 belongs to new solution of the present utility model, 5 to 10 for vacuumize, filling with inert gas protection, thermometric, the employed all purpose instrument of these a series of routine operations of measuring resistance.

Embodiment:

Device main body is the connection container that is welded with three sections stainless-steel tubes.The internal diameter of measuring tube is 3.5mm, and length is 190mm, and tube wall is 0.5mm.The sealing of one end, the other end is connected in the homogenising chamber.Be welded with 5 nickel filaments on the measuring tube lateral surface and make contact conductor.Conducting a survey near a contact conductor special use of blind end, whether sample has been filled into all the other four corresponding positions of electrode in the measuring tube.In addition four contact conductors are connected on the electric bridge resistance with the four probe method measuring samples of routine.The homogenising chamber is a closed at both ends, but side and end face respectively have the stainless-steel tube of a little opening, and its internal diameter is 25mm, and length is 65mm.With the homogenising chamber end face of the same end of measuring tube opening on, be welded with connecting pipe, its internal diameter is 6mm, length is 800mm.The other end of connecting pipe connects a stop,threeway by a vacuum rubber pipe, and two outlets of all the other of this piston are connected to vacuum pump and inert gas gas cylinder respectively.A thermopair is placed at the middle part of measuring tube, and thermopair is connected to digital voltmeter to measure temperature.

The utility model is operated easily.During use, unplug the vacuum rubber pipe, connecting pipe is erected put, proportionately the proportion by subtraction confected materials is added to the homogenising chamber from connecting the mouth of pipe.Connect the vacuum rubber pipe again and vacuumize, logical argon gas, repeated multiple times is caught up with most remnant oxygen.Crucible oven is put in the homogenising chamber, and under argon shield, heating, insulation make sample melt and reach homogenization of composition in the homogenising chamber.After treating the alloying component homogenising, vacuumize, this device is moved into horizontal temperature control furnace from crucible oven, keeping under the situation of measuring tube below being in, device is horizontally-arranged in the stove, shakes connecting pipe gently, make the gravity of sample dependence own flow into measuring tube from the homogenising chamber.Applying argon gas again.Measure the resistance that has filled the stainless-steel tube of sample near the inside between two contact conductors of outermost of measuring tube blind end, compare, to determine whether sample has been filled into the corresponding position of four point probe in the measuring tube with the resistance that blank pipe records.As do not reach requirement, then device to be taken out from stove.Perpendicular putting vacuumizes, and makes sample flow back to the homogenising chamber, repeats above operation again, up to sample has flow to the corresponding position of four point probe in measuring tube till.Just can change the resistance of temperature survey sample this moment.

Claims (2)

1. one kind has fully and is welded by stainless-steel tube, have the measurement mechanism of the resistance of the molten metal of combination container of sample composition homogenising and two functions of resistance measurement and alloy, it is characterized in that forming by measuring tube (1), contact conductor (2), homogenising chamber (3) and connecting pipe (4) and external optional equipment;

2. according to the said measurement mechanism of claim 1, it is characterized in that:

A. measuring tube, homogenising chamber and connecting pipe all are stainless-steel tubes, and measuring tube and connecting pipe all weld together with the homogenising chamber, become connection container;

B. measuring tube one end sealing, during measurement, measuring tube is horizontally-arranged;

C. be welded with five contact conductors on the measuring tube, wherein a contact conductor near blind end is used for checking whether the sample of fusing has been filled into the corresponding position of measuring tube four point probe;

D. the measuring tube internal diameter is 〉=3 to 6mm, and length is 〉=60 to 200mm, and tube wall is 〉=0.3 to 1mm;

E. homogenising chamber volume is 〉=5 to 60cm ³