| 摘要 |
The method comprises: (a) providing a material in the form of powder particles; (b) heating a first quantity of the powder to a temperature higher than a melting point of the powder using a high energy beam (95) and forming a first bath comprising the melted powder and a portion of a support member (80) at a surface of the support member; (c) heating a second quantity of the powder and forming a second bath including the melted powder downstream of the first bath at the support member surface; and (d) repeating the step (c) until a first layer (10) of the part is formed on the support member. The method comprises: (a) providing a material in the form of powder particles; (b) heating a first quantity of the powder to a temperature higher than a melting point of the powder using a high energy beam (95) and forming a first bath comprising the melted powder and a portion of a support member (80) at a surface of the support member; (c) heating a second quantity of the powder and forming a second bath comprising the melted powder downstream of the first bath at the surface of the support member; (d) repeating the step (c) until a first layer (10) of the part is formed on the support member; (e) heating an n-th quantity of powder and forming an n-th bath comprising the melted powder above a portion of the first layer; (f) heating an [n+1]th quantity of the powder and forming an [n+1]th bath comprising the melted powder downstream of the [n]th bath; repeating the step (f) in order to form a second layer (20) of the part above the first layer; and (h) repeating the steps (e) to (g) for each layer located above an already formed layer until the part reaches the final form. During the formation of each of the baths, back-up heating is used to heat the material located in an area adjacent to the bath to a temperature lower than the melting point, where the area comprises a region selected between a region upstream of the bath and a region downstream of the bath. The material in the upstream region is heated so as to reduce a cooling rate of the material below its natural cooling rate. The material in the downstream region is heated so as to reduce the heating rate of the material below its natural speed of heating up to the melting point. The material in a portion of the region adjacent to the bath is heated at a temperature between a third and half of the melting point. The material is heated using a heating unit comprising an oven, a hot plate, an inductor, and the high energy beam. The material is heated using a defocused part of the high energy beam. After the step (h), the remelting of parts of the outermost layer of the part is carried out using the high energy beam so as to reduce some open pores and closed pores on the surface of the part. A hot hydrostatic pressing is performed on the part so as to reduce the porosity in the part. An independent claim is included for an apparatus for manufacturing a part. |
