SU935208A1

SU935208A1 - Mould for casting high-melting alloys

Info

Publication number: SU935208A1
Application number: SU802981631A
Authority: SU
Inventors: Даниил Макарович Колотило; Валерий Иосифович Полищук; Владлен Трофимович Яковлев; Борис Изосимович Чирков; Наталья Николаевна Бутарова; Валерий Григорьевич Клочихин
Original assignee: Институт проблем литья АН УССР
Priority date: 1980-09-12
Filing date: 1980-09-12
Publication date: 1982-06-15

Description

Изобретение относитс к литейному производству, а именно к производству отливок из высокореакционных туго плавких металлов.FIELD OF THE INVENTION The invention relates to a foundry, namely the production of castings from highly reactive, hard-fusible metals.

Известны посто нные металлические формы, выполненные из высокотеплопроводных материалов, например из меди и ее сплавов II.Permanent metallic forms made of highly heat-conducting materials, such as copper and its alloys II, are known.

При литье в такие формы в отливках возникают значительные внутренние напр жени , св занные с затрудненной усадкой, что приводит к короблению отливок и деформации нагруженных узлов формы.When casting into such molds, significant internal stresses occur in castings associated with hindered shrinkage, which leads to buckling of the castings and deformation of the loaded shape nodes.

Наиболее близкой к предлагаемой по технической сущности форма дл лить тугоплавких сплавов, содержаща металлические полуформы и вставки из графитоуглеродных материалов 2 .Closest to the proposed technical essence of the form for casting refractory alloys containing metal molds and inserts of graphite carbon materials 2.

Недостатками этой формы вл етс ее деформируемость, свариваемость с заливаемым сплавом и низкое качество получаемых отливок.The disadvantages of this form are its deformability, weldability with the cast alloy and the low quality of the castings produced.

Цель изобретени - предотвращение деформации формы и ее свариваемости с заливаемым сплавом и повышение качества отливки.The purpose of the invention is to prevent deformation of the form and its weldability with the cast alloy and improving the quality of the casting.

Поставленна цель достигаетс тем, что в форме дл лить тугоплавних сплавов, содержащей металлические полуформы и вставки из графитоуглеродных материалов, последние установлены в термически нагруженных и преп тствук цих усадке част х с одной степенью свободы перемещени в направлении усадки отливок.This goal is achieved by the fact that in the form for casting refractory alloys containing metal half-molds and inserts of graphite-carbon materials, the latter are installed in thermally loaded and preventive shrink parts with one degree of freedom of movement in the direction of the shrinkage of the castings.

На фиг.1 изображена форма; на фиг.2 - вид А на фиг.1.Figure 1 shows the form; figure 2 - view And figure 1.

10ten

При заливке расплавом форма быстро нагреваетс и увеличивает свои геометрические размеры соответственно коэффициенту линейного термического расширени материала, из ко15 торого она изготовлена. В то же врем отливка, кристаллизу сь и охлажда сь , уменьшаетс в размерах.When melt is poured, the mold quickly heats up and increases its geometrical dimensions according to the coefficient of linear thermal expansion of the material from which it is made. At the same time, the casting, crystallizing and cooling, is reduced in size.

Свободна линейна усадка отливок из тугоплавких металлов находитс в Free linear shrinkage of refractory metal castings is found in

20 пределах 1,5-2,5%,а термическое расширение меди (материала формы) при нагреве до контактных температур (300-500°С) не превышает 2%, т.е. суммарна разница геометрических 20 within 1.5-2.5%, and the thermal expansion of copper (mold material) when heated to contact temperatures (300-500 ° C) does not exceed 2%, i.e. total geometric difference

25 размеров соответствующих фрагментов формы и отливки может достигать 4,5-5% или 1/20 длины отливки или рабочей поверхности формы. Устанавлива в медной форме в местах затруд-. The 25 sizes of the respective mold fragments and castings can reach 4.5-5% or 1/20 of the casting length or working surface of the mold. Installing in copper form in places difficult.

Claims

thirty . Forced shrinkage of the casting, movable inserts made of graphite-carbon materials (pressed or turned) prevent mold deformation and casting, as well as their welding. Graphite-carbon inserts perceive deformation loads. At the same time, they are either elastically deformed (the elastic deformation of dense graphite reaches 25%), or they move along the surface of the mold by the length of the essential change in the geometric dimensions of the mold and the casting, remove almost all the tension of the casting to the mold, which is especially important when getting thin-walled . . Example. Form I for casting titanium-based alloys, which are flat plates 2 with a length of 400 mm with locking grooves, which are difficult to shrink, are made of copper with graphite inserts 3 forming locking grooves. The graphite inserts are mounted on the copper half-form in the landing slots 4, which allow one-sided movement of the inserts, at the same time they are installed taking into account the freedom of movement towards the free linear shrinkage of the casting. The length of the free movement of each graphite insert along the nest in this case is in the limit of 10 mm, since the part is symmetrical and the movement of both inserts completely compensates for the changes in the dimensions of the CAST and FO {RI | Y. The casting obtained in this form has a smooth surface, and at the points of the three-slotted grooves, its interaction with the mold is not observed. Casting junk is eliminated. The geometrical dimensions of the mold after a series of test fillings remain unchanged. Experiments have shown that such forms are suitable for repeated use. The expected economic effect, according to preliminary calculations, on the use of these forms for the production of shaped Pouring from niobium alone is 50 thousand rubles. per year due to the transfer of casting from single forms to permanent ones, which entails a decrease in total labor costs by about 2-2.5 times, a reduction in the cost of molding materials by 80% and a reduction in scrap casting by 12-15% g Invention Form for casting refractory alloys containing metal semi-forms and inserts of graphite carbon materials, characterized in that, in order to prevent deformation of the form and its weldability with the cast alloy and improve the quality of the castings, the inserts are installed in thermally loaded and preventable debris x shape with one degree of freedom of movement in the direction of casting shrinkage. Sources of information taken into account in the examination 1. For France of France 2400401, cl. C 22 C 9/00, 1979.

2.Gul ev B.B. and others. Special ways to pour. L., Mechanical Engineering, 1971, p. 169-174.