CN-122007382-A - Bipolar zigzag directional solidification casting heating device and use method

CN122007382ACN 122007382 ACN122007382 ACN 122007382ACN-122007382-A

Abstract

The invention discloses a bipolar zigzag directional solidification casting heating device and a using method thereof, wherein the bipolar zigzag directional solidification casting heating device comprises a heat insulation component, heating components, temperature control components and conducting components, wherein the heat insulation component is arranged in a heat insulation cavity in a surrounding mode, the heat insulation component is used for conducting radiation heating on in-line casting modules extending into the heat insulation cavity, the heating components are divided into an upper zone heating group and a lower zone heating group along the height direction, each heating group comprises a left electrode heating component and a right electrode heating component which are oppositely arranged and are mutually electrically isolated, so that four mutually electrically isolated closed electric heating loops are formed, heating plates in the left electrode heating component and the right electrode heating component are staggered in a zigzag mode, the outlines of the heating plates on the left side and the right side are opposite to each other, a plurality of diamond heating spaces for accommodating single castings are formed, the temperature control components are provided with temperature measuring points corresponding to the four closed electric heating loops respectively, are used for collecting temperature feedback signals of the loops and conducting independent closed loop adjustment on heating currents of the loops, and the conducting components are electrically connected with the heating components and are used for connecting an external power supply. The invention aims to enable the heating structure to realize uniform heating in multiple direction dimensions, realize relatively symmetrical strong radiation heat exchange in all directions, improve the uniformity of a temperature field and reduce the risks of defects such as mixed crystals, freckles and the like.

Inventors

WANG FU
XIE WEINING
LIU YANG
CHEN XIAORUI
SONG HAIYANG
SHANG YAN
YANG QIANG
YAN ZHAN

Assignees

西安交通大学

Dates

Publication Date: 20260512
Application Date: 20260211

Claims (10)

1. A bipolar zigzag directional solidification casting heating device, comprising: the heat insulation assembly (101) is surrounded to form a heat insulation cavity; the heating component (103) is arranged in the heat-preserving cavity and used for carrying out radiation heating on the in-line casting module extending into the heat-preserving cavity; The heating assemblies (103) are divided into an upper zone heating group and a lower zone heating group along the height direction, and each heating group comprises a left electrode heating assembly and a right electrode heating assembly which are oppositely arranged and electrically isolated from each other, so that four closed electric heating loops electrically isolated from each other are formed; The heating plates (301) in the left electrode heating assembly and the right electrode heating assembly are staggered in a zigzag manner, so that the outlines of the heating plates (301) on the left side and the right side are opposite to each other and a plurality of diamond-shaped heating spaces for accommodating single castings are formed; The temperature control assembly (102) is provided with temperature measuring points corresponding to the four closed electric heating loops respectively and is used for collecting temperature feedback signals of the loops and independently performing closed-loop adjustment on heating current of the loops; And the conductive component (104) is electrically connected with the heating component (103) and is used for being connected with an external power supply.
2. The bipolar zigzag directional solidification casting heating apparatus according to claim 1, wherein the heating plates (301) are arranged in pairs in a single electrode heating assembly so as to be perpendicular to each other and in a staggered arrangement.
3. The bipolar zigzag directional solidification casting heating device according to claim 1, wherein the temperature control assembly (102) comprises four groups of platinum-rhodium thermocouples (201) respectively arranged at temperature measuring points of the four closed electric heating loops, and the heating current of the corresponding loops is independently adjusted by adopting a PID control algorithm based on signals of the thermocouples.
4. The bipolar zigzag directional solidification casting heating device according to claim 1, wherein the heating component (103) is mounted on the heat insulation component (101) through a graphite electrode (305), the graphite electrode (305) penetrates through the side wall of the heat insulation component (101), one end of the graphite electrode is electrically connected with a heating plate (301), the other end of the graphite electrode is electrically connected with the conductive component (104), a screw thread and an adjusting nut (304) matched with the screw thread are arranged on the graphite electrode (305), and the mounting position of the heating component (103) in the heat insulation cavity can be adjusted by adjusting the locking position of the adjusting nut (304) and the clamping position of the graphite electrode (305) on the conductive component (104).
5. The bipolar zigzag directional solidification casting heating apparatus according to claim 4, wherein the conductive assembly (104) comprises a conductive block body (401) and a clamping mechanism (403), wherein a cooling flow passage (402) is arranged inside the conductive block body (401), and wherein the graphite electrode (305) is adjustably mounted in the clamping mechanism (403).
6. The bipolar zigzag directional solidification casting heating device according to claim 5, wherein the conductive assembly (104) further comprises a current guiding flange (405), wherein a cooling medium inlet and a cooling medium outlet are provided on the current guiding flange (405) and are communicated with the cooling flow channel (402), wherein the cooling medium inlet is positioned below, and the cooling medium outlet is positioned above.
7. The bipolar zigzag directional solidification casting heating device according to claim 1, wherein the insulation assembly (101) is comprised of a plurality of hard carbon mats.
8. The bipolar zigzag directional solidification casting heating device according to claim 1, wherein the heating plate (301) is made of carbon fiber material.
9. A method of directional solidification casting using the bipolar saw tooth directional solidification casting heating apparatus as claimed in any one of claims 1-8, comprising: placing casting modules arranged in series in the heat preservation cavity, so that each casting is positioned in the central area of one diamond-shaped heating space; According to the width of the casting module, the position of the heating component (103) is adjusted to enable the heating plate (301) to reach the preset radiation distance with the casting module; The heating component (103) is powered by the conductive component (104), and the four closed electric heating loops are subjected to independent PID temperature control by the temperature control component (102), so that the temperature of the heat preservation cavity is raised to the target temperature or is raised according to the target temperature raising rate; pouring molten metal into the preheated casting mould set, and drawing to finish directional solidification.
10. The method of claim 9, wherein the step of adjusting the position of the heating assembly (103) comprises loosening the adjustment nut (304), adjusting the extension of the graphite electrode (305) in the clamping mechanism (403), and then re-locking the adjustment nut (304).

Description

Bipolar zigzag directional solidification casting heating device and use method Technical Field The invention relates to the technical field of metal casting, in particular to a bipolar zigzag directional solidification casting heating device and a using method thereof. Background Currently, high-speed solidification (HRS, high Rate Solidification) is mainly used in industrial production to manufacture single crystal turbine blades. In the technology, the heater structure of the vacuum directional solidification furnace is barrel-shaped or annular, and in order to realize the efficient preparation of the monocrystalline blade, the ceramic mould shell for casting the high-temperature alloy monocrystalline blade also needs to form an annular blade mould shell group so as to be cast and formed at one time. However, due to the shielding of radiation between the annular mould shell groups, the side of the mould shell facing away from the heater is difficult to obtain the same direct radiation heating condition as the side facing the heater, so that the phenomenon of inner side heat exchange hysteresis occurs in the casting in the directional solidification process, and the solid-liquid interface isotherm is seriously bent and inclined in the transverse scale range. In order to solve the above problems, a parallel heater structure has been proposed, and the modules are arranged in a single row or in parallel, so that the two sides of each casting obtain relatively symmetrical heating conditions, thereby effectively reducing the adverse effect caused by the shadow effect of the annular heater of the traditional HRS device. However, the parallel heater can only ensure that the two sides of the casting, which directly face the heater, have relatively symmetrical heating conditions, but the corresponding two sides between the casting and the casting cannot be directly heated by radiation of the heater, so that the consistency of the heating conditions is difficult to ensure, and the inclination of the isotherm of the solid-liquid interface is still possible. Therefore, there is still a need for a directional solidification casting heating device that enables a heating structure to achieve uniform heating in multiple directional dimensions, achieves relatively symmetrical strong radiation heat exchange in all directions, improves temperature field uniformity, and reduces the risk of defects. Disclosure of Invention Aiming at the problems in the prior art, the invention provides a bipolar zigzag directional solidification casting heating device and a use method thereof, and aims to enable a heating structure to realize uniform heating in multiple direction dimensions, realize relatively symmetrical strong radiation heat exchange in all directions, improve the uniformity of a temperature field and reduce the risks of defects such as mixed crystals, freckles and the like. In order to solve the technical problems, the invention is realized by the following technical scheme: according to a first aspect of the present invention there is provided a bipolar zigzag directional solidification casting heating apparatus comprising: The heat insulation assembly is surrounded to form a heat insulation cavity; The heating component is arranged in the heat preservation cavity and used for carrying out radiation heating on the in-line casting module extending into the heat preservation cavity; the heating assembly is divided into an upper zone heating assembly and a lower zone heating assembly along the height direction, and each heating assembly comprises a left electrode heating assembly and a right electrode heating assembly which are oppositely arranged and electrically isolated from each other, so that four closed electric heating loops electrically isolated from each other are formed; The heating plates in the left electrode heating assembly and the right electrode heating assembly are staggered in a zigzag manner, so that the outlines of the heating plates on the left side and the right side are opposite to each other and a plurality of diamond-shaped heating spaces for accommodating single castings are formed; The temperature control assembly is provided with temperature measuring points corresponding to the four closed electric heating loops respectively and is used for collecting temperature feedback signals of the loops and independently performing closed loop adjustment on heating current of the loops; And the conductive component is electrically connected with the heating component and is used for accessing an external power supply. In a possible implementation manner of the first aspect, the heating plates are arranged in pairs in a single electrode heating assembly to be perpendicular to each other and arranged in a staggered manner. In a possible implementation manner of the first aspect, the temperature control assembly includes four groups of platinum-rhodium thermocouples respectively disposed at temperature measuri