CN103741039A - Preparation method of locomotive brake resistance band with good resistance uniformity - Google Patents

Abstract

The invention relates to a locomotive brake resistance band and a preparation method thereof. The resistance band contains the following main ingredients in percentage by weight: 13.5-14.5% of chromium, 3.5-4.5% of aluminum, 0.25-0.35% of titanium, not higher than 0.04% of carbon, 0.05-0.10% of rare earth and the balance of iron. The preparation method of the resistance band sequentially comprises the steps of carrying out vacuum smelting, carrying out electroslag remelting, forging, carrying out hot-rolling, carrying out annealing heat treatment, pickling, polishing to trim, carrying out cold-rolling, carrying out gas-shielding annealing and carrying out striping forming. The locomotive brake resistance band disclosed by the invention is made from ferrite alloy, and metal nickel is not used any more, so that the production cost can be reduced greatly; the elemental titanium is adopted, so that the resistance uniformity of the resistance band can be improved, meanwhile, the temperature coefficient of resistance of the resistance band can be lowered, and then, the quality of a product is improved. The preparation method comprises the working procedure of vacuum smelting, so that the content of air in the prepared resistance band can be relatively low, and the purity of the product is ensured.

Description

A kind of preparation method of locomotive braking resistance belt of resistance good uniformity

The application divides an application, the application number of original application: 201110230208.9, the applying date: 2011-08-11, invention and created name < < locomotive braking resistance belt and preparation method thereof > >.

Technical field

The present invention relates to alloy and manufacture craft thereof, specifically a kind of locomotive braking resistance belt and preparation method thereof.

Background technology

On trunk railway diesel-electric locomotive, all adopt resistive braking device, because locomotive is to take diesel engine as power, through flexible coupling, be connected with main generator, the electricity sending through electrical control cubicles for train wheel on traction electric machine electrical source of power is provided; Traction electric machine is passed to wheel through driving toothed gear upper follower gear is driven to wheel train operation, and whole process is the journey that turns over of mechanical energy--electric energy--mechanical energy.Locomotive is when braking, because the rotor speed of traction electric machine is higher than stator rotatingfield rotating speed, traction electric machine becomes electromagnetic power output state (that is: generator condition) by electromagnetic power input state, to to the locomotive power of having the opposite effect, be the damping force of train, this part alternating-current is after the rectification of thermal change device, directly add to braking resistor energy transform into heat energy, the cooling air being blown into through blower fan is taken away and is consumed.This is the conversion process of a mechanical energy--electric energy--heat energy.

The resistive band adopting in braking resistor of the prior art, often adopts nickel alloy material to make, and cost is higher.For example: the locomotive brake braking resistance alloy that the conventional trade mark is N40 in the market, its chief component composition and content are: Ni:34.0-37.O%, Cr:18.0-21.0%, Si:1.0-3.0%, C≤0.10%, Mn≤1.00%, Al≤0.05%, Fe: surplus, but because the content of nickel is higher, cause its price too high; Also having a kind of trade mark is the stainless steel materials of 310S, its chief component composition is: Ni:19.0-22.0%, Cr:24.0-26.0%, Si :≤1.5%, C≤0.08%, Mn≤2.00%, Fe: surplus, although it has reduced the usage quantity of Ni, overall cost is still higher, and resistivity only has 0.95uQm, be not suitable as locomotive brake braking resistive band.

Summary of the invention

The technical problem to be solved in the present invention is to provide locomotive braking resistance belt of a kind of lower cost and preparation method thereof.

In order to solve the problems of the technologies described above, the invention provides a kind of locomotive braking resistance belt, it each predominant quantity degree comprising is: chromium: 13.5-14.5%, aluminium: 3.5-4.5%, titanium: 0.25-0.35%, carbon :≤0.04%, rare earth: 0.05-0.10%, iron: surplus.

 

The preparation method of above-mentioned locomotive braking resistance belt, comprises following operation: vacuum melting successively; Esr; Forge; Hot rolling; Annealing thermal treatment; Pickling; Polishing deburring; Cold rolling; Gas shield annealing; Itemize moulding.

Technique scheme of the present invention has the following advantages compared to existing technology: the locomotive braking resistance belt in (1) the present invention is Alfer, do not re-use metallic nickel, can significantly reduce production costs, be the performance that the locomotive brake braking of N40 has with resistance alloy but can keep the trade mark.(2) in locomotive braking resistance belt of the present invention, adopted titanium elements, can improve the resistance homogeneity of resistive band, can reduce the temperature coefficient of resistance of this resistive band simultaneously, avoided the considerable influence of temperature variation to resistive band resistance, and then improved product quality.In addition, also added rare earth element, it is suitable for making the alloying performance of resistive band better.(3) preparation method of locomotive braking resistance belt comprises vacuum melting operation, and the abundant content of air in the resistive band that can make to generate is less, has guaranteed the purity of product.

Embodiment

Embodiment 1

Each predominant quantity degree that the locomotive braking resistance belt of the present embodiment comprises is: chromium: 13.5%, and aluminium: 4.5%, titanium: 0.35%, carbon :≤0.04%, rare earth: 0.05%, iron: surplus.

Embodiment 2

Each predominant quantity degree that the locomotive braking resistance belt of the present embodiment comprises is: chromium: 14%, and aluminium: 4.0%, titanium: 0.30%, carbon :≤0.03%, rare earth: 0.07%, iron: surplus.

 

Embodiment 3

Each predominant quantity degree that the locomotive braking resistance belt of the present embodiment comprises is: chromium: 14.5%, and aluminium: 3.5%, titanium: 0.25%, carbon :≤0.02%, rare earth: 0.10%, iron: surplus.

Embodiment 4

The preparation method of the locomotive braking resistance belt in the various embodiments described above comprises following operation successively:

Vacuum melting; Esr; Forge; Hot rolling; Annealing thermal treatment; Pickling; Polishing deburring; Cold rolling; Gas shield annealing; Itemize moulding.

Wherein: the vacuum induction melting furnace that vacuum melting operation adopts east, Jinzhou metallurgical technology research company limited to produce, model ZG-0.5LB.Smelting temperature is 1500-1650 ℃ (the best is 1580 ℃); Vacuum tightness≤0.13Pa.

Described gas shield annealing operation comprises: adopt continous way gas shield bright heat treatment electric furnace, final annealing and destressing for resistive band are processed, product enters burner hearth and reaches gas shield effect at (mol ratio: hydrogen 75%, the nitrogen 25%) mixed gas decomposing through liquefied ammonia, whole annealing furnace take before, during and after three districts temperature controls operations, product You Yi district enters boiler tube and heats up, length is 3 meters, 850 ℃ of temperature controls; Two section length are 2 meters, and 800 ℃ of temperature controls, carry out heat preservation hot processing; 3rd district, length is 750 ℃ of 3 meters of temperature controls, carries out preserving temperature and reducing temperature processing; Whole production line carries out under the linear velocity of 5-6 m/min, product after this equipment thermal treatment, surface-brightening, non-oxidation phenomenon, handled good product consistency.

The semicontinuous vacuum induction melting furnace of ZG-0.5LB is mainly used in all kinds of superalloys, Precise Alloy; iron-based, nickel-base alloy and some non-ferrous metal and alloy thereof, under vacuum state or protection of inert gas, utilize the principle of Frequency Induction Heating to melt, smelting, cast molding.This stove is except possessing the whole features of general vacuum induction furnace, between feeding chamber and melting storehouse, melting storehouse and ingot mould storehouse, with valve, separate, therefore can be not destroying feed in raw material under vacuum condition (thermometric), melting, ingot casting is cooling and go out ingot, realizes semicontinuous production.

The use temperature of the semicontinuous vacuum induction melting furnace of ZG-0.5LB generally depends on crucible material, and when doing crucible material with magnesium oxide, smelting temperature can reach 1800 ℃; While doing crucible material with zirconium white, can reach 1900 ℃, and when reaching 2500 ℃ with plumbago crucible, user can select crucible material kind according to the material of own melting.

The semicontinuous vacuum induction furnace of ZG-0.5LB by electric furnace body, intermediate frequency (IF) smelting power supply, electric control system, vacuum system, enter electric system, furnace tilting mechanism, inductor block, segregaion valve, hydraulic efficiency system, pneumatic system, water-cooling system and form, be provided with in addition workplatform etc.

Described esr operation comprises:

1, the allotment of striking agent and remelting electroslag system: prepare striking agent with fluorite and titanium dioxide, use CaF ₂, Al ₂o ₃make remelting electroslag system with CaO;

2, shove charge: chassis, striking agent, crystallizer and electrode are installed;

3, striking slag making: reduce electrode electrode is contacted with striking agent, complete striking work, make striking agent fusing, add remelting electroslag system;

4, smelt: control electric current 2400-2800A, voltage 38-41V, makes electrode melting, until crystallizer is filled;

5, cooling: after having smelted, remelting steel ingot takes off ingot air cooling in crystallizer after cooling 30 minutes;

The described operation that forges comprises:

1, heating: charging temperature :≤850 ℃, the heating-up time: >=60 minutes, Heating temperature: 1180-1250 ℃, soaking time: >=50 minutes, initial forging temperature: >=1150 ℃, final forging temperature: >=950 ℃;

2, forging: forging adopts the second light industry bureau one weight, and two even methodologys, start to touch with less deflection, etc. plasticity, improve the rear bang of taking the circumstances into consideration, while closing on final forging temperature, touch again, deformation requirements is even, avoid repeatedly clashing at same position, it is wide that each feed should be less than brill, and each feed should be greater than draught, avoids producing folding, when steel ingot forges, first forge microcephaly, it is qualified that microcephaly forges size, then turn forging major part around;

Described hot-rolled process comprises:

Charging temperature :≤850 ℃;

Heating-up time: >=50 minutes;

Heating temperature: 1180-1250 ℃;

Soaking time: >=50 minutes;

Initial forging temperature: >=1150 ℃;

Final forging temperature: >=950 ℃;

Described annealing heat treatment step: thermal treatment temp is 780 ℃, is incubated 5 hours;

Described pickling process: extremely white with sulfuric acid immersion, salt acid rinse, pickling temperature 50-80 ℃, pickling time 20-30min.

Performance test table:

Test event	310S	N40	Example 1	Example 2	Example 3	Example 4	Example 5
								Resistance temperature variation factor (1000 ℃)	1.295	1.219	1.13	1.13	1.13	1.12	1.13
Elongation	≥21	≥22	22	23	22	23	23
								Resistivity	0.95	1.04	1.24	1.24	1.25	1.23	1.24
Element maximum operation (service) temperature	950	1000	1200	1200	1200	1200	1200

Obviously, above-described embodiment is only for example of the present invention is clearly described, and is not the restriction to embodiments of the present invention.For those of ordinary skill in the field, can also make other changes in different forms on the basis of the above description.Here exhaustive without also giving all embodiments.And these belong to apparent variation that spirit of the present invention extended out or change still among protection scope of the present invention.

Claims (1)

1. a preparation method for locomotive braking resistance belt, is characterized in that:

Each predominant quantity degree of described locomotive braking resistance belt is:

Chromium: 13.5-14.5%,

Aluminium: 3.5-4.5%,

Titanium: 0.25-0.35%,

Carbon :≤0.04%,

Rare earth: 0.05-0.10%,

Iron: surplus;

The preparation method of above-mentioned locomotive braking resistance belt comprises following operation successively:

Vacuum melting;

Esr;

Forge;

Hot rolling;

Annealing thermal treatment;

Pickling;

Polishing deburring;

Cold rolling;

Gas shield annealing;

Itemize moulding;

Adopt continous way gas shield bright heat treatment electric furnace, product entered to burner hearth at the mixed gas decomposing through liquefied ammonia, to reach gas shield effect, whole annealing furnace take before, during and after the temperature controls operation of 3rd district; Product is 3 meters by a section length, 850 ℃ of temperature controls; Two section length are 2 meters, and 800 ℃ of temperature controls, to carry out heat preservation hot processing; Three section length are 3 meters, and 750 ℃ of temperature controls, to carry out preserving temperature and reducing temperature processing; Whole production line carries out under the linear velocity of 5-6 m/min;

Described esr operation comprises:

(1), the allotment of striking agent and remelting electroslag system: prepare striking agent with fluorite and titanium dioxide, use CaF ₂, Al ₂o ₃make remelting electroslag system with CaO;

(2), shove charge: chassis, striking agent, crystallizer and electrode are installed;

(3), striking slag making: reduce electrode electrode is contacted with striking agent, complete striking work, make striking agent fusing, add remelting electroslag system;

(4), smelt: control electric current 2400-2800A, voltage 38-41V, makes electrode melting, until crystallizer is filled;

(5), cooling: after having smelted, remelting steel ingot takes off ingot air cooling in crystallizer after cooling 30 minutes.