Aluminum alloy airfoil with designed crystallographic texture

An airfoil includes an airfoil body that extends at least between leading and trailing edges, first and second sides, and radially inner and outer ends. The airfoil body includes an aluminum alloy that has a controlled crystallographic texture with respect to a predefined three-dimensional coordinate system. The airfoil can be used in the fan of a gas turbine engine.

BACKGROUND

SUMMARY

An airfoil according to an example of the present disclosure includes an airfoil body extending at least between leading and trailing edges, first and second sides, and radially inner and outer ends. The airfoil body includes an aluminum alloy having a controlled crystallographic texture with respect to a predefined three-dimensional coordinate system.

In a further embodiment of any of the foregoing embodiments, the three-dimensional coordinate system has an axis extending in a radial direction with respect to the radially inner and outer ends.

In a further embodiment of any of the foregoing embodiments, the controlled crystallographic texture includes 20 to 100% of crystallites by volume oriented of a high strength crystal direction within 10° radius of an axis of the predefined three-dimensional coordinate system.

In a further embodiment of any of the foregoing embodiments, the high strength crystal direction is selected from the group consisting of <111>, <112> and <110>.

In a further embodiment of any of the foregoing embodiments, the predefined three-dimensional coordinate system is a Cartesian coordinate system having a Z-axis extending along a radial direction of the airfoil body, a X-axis extending in a direction traverse to the first and second sides, and an Y-axis extending orthogonally to the Z-axis and the X-axis, and the controlled crystallographic texture includes an orientation of a selected crystal direction within a cone of 10° of the Z-axis.

In a further embodiment of any of the foregoing embodiments, the selected crystal direction is selected from the group consisting of <111>, <112>, <110>, and combinations thereof.

In a further embodiment of any of the foregoing embodiments, the predefined three-dimensional coordinate system is a Cartesian coordinate system having a Z-axis extending along a radial direction of the airfoil body, an X-axis extending in a direction traverse to the first and second sides, and a Y-axis extending orthogonally to the Z-axis and the X-axis, and the controlled crystallographic texture includes orientations of at least one of crystal directions <111>, <112> and <110> within 10° with respect to at least one of the axes of the Cartesian coordinate system.

In a further embodiment of any of the foregoing embodiments, the controlled crystallographic texture defines a texture distribution with respect to volume fractions of textures.

In a further embodiment of any of the foregoing embodiments, the texture distribution includes 20% to 100%, by volume, of a defined texture.

In a further embodiment of any of the foregoing embodiments, the predefined three-dimensional coordinate system is a Cartesian coordinate system having a Z-axis extending along a radial direction of the airfoil body, a X-axis extending in a direction traverse to the first and second sides, and an Y-axis extending orthogonally to the Z-axis and the X-axis, and the texture distribution includes 30% to 70%, by volume, of a first texture, the first texture being defined by a {111} type of crystallographic plane being parallel within +/−10° of the X-Y, X-Z or Z-Y plane of the Cartesian coordinate system and a <1-10> type of crystallographic direction being oriented within a cone of 10° of one of the axes of the Cartesian coordinate system.

In a further embodiment of any of the foregoing embodiments, the texture distribution further includes 30% to 70%, by volume, of a second texture, the second texture being defined by a {111} type of crystallographic plane being parallel within +/−10° of the X-Y, X-Z or Z-Y plane of the Cartesian coordinate system and a <−110> type of crystallographic direction being oriented within a cone of 10° of one of the axes of the Cartesian coordinate system.

In a further embodiment of any of the foregoing embodiments, the texture distribution further includes less than 40%, by volume, of a third texture, the third texture being defined by a {100} crystallographic plane being parallel within +/−10° of the X-Y, X-Z or Z-Y plane of the Cartesian coordinate system and a <001> crystallographic direction being oriented within a cone of 10° of one of the axes of the Cartesian coordinate system.

A gas turbine engine according to an example of the present disclosure includes a fan, a compressor section, a combustor in fluid communication with the compressor section, and a turbine section in fluid communication with the combustor. The fan includes an airfoil having an airfoil body extending at least between a leading edge and a trailing edge, a first side and a second side, and a radially inner end and a radially outer end. The airfoil body includes an aluminum-based metallic material having a controlled crystallographic texture with respect to a predefined three-dimensional coordinate system.

In a further embodiment of any of the foregoing embodiments, the controlled crystallographic texture includes an orientation of a high strength crystal direction within 10° of an axis of the predefined three-dimensional coordinate system.

In a further embodiment of any of the foregoing embodiments, the predefined three-dimensional coordinate system is a Cartesian coordinate system having a Z-axis extending along a radial direction of the airfoil body, a X-axis extending in a direction traverse to the first and second sides, and an Y-axis extending orthogonally to the Z-axis and the X-axis, and the controlled crystallographic texture includes an orientation of a selected crystal direction within a cone of 10° of the Z-axis.

In a further embodiment of any of the foregoing embodiments, the selected crystal direction is selected from the group consisting of <111>, <112>, <110>, and combinations thereof.

In a further embodiment of any of the foregoing embodiments, the predefined three-dimensional coordinate system is a Cartesian coordinate system having a Z-axis extending along a radial direction of the airfoil body, a X-axis extending in a direction traverse to the first and second sides, and an Y-axis extending orthogonally to the Z-axis and the X-axis, and the controlled crystallographic texture includes orientations of at least one of crystal directions <111>, <112> and <110> within a cone of 10° with respect to at least one of the axes of the Cartesian coordinate system.

In a further embodiment of any of the foregoing embodiments, the controlled crystallographic texture defines a texture distribution with respect to volume fractions of texture components.

In a further embodiment of any of the foregoing embodiments, the texture components distribution includes 20% to 100%, by volume, of a defined texture.

In a further embodiment of any of the foregoing embodiments, the predefined three-dimensional coordinate system is a Cartesian coordinate system having a Z-axis extending along a radial direction of the airfoil body, an X-axis extending in a direction traverse to the first and second sides, and a Y-axis extending orthogonally to the Z-axis and the X-axis, and the texture component distribution includes:

30% to 70%, by volume, of a first texture components, the first texture component being defined by a {111} crystallographic plane of the crystallites in this component being parallel within +/−10° of the X-Y, X-Z or Z-Y plane of the Cartesian coordinate system and a <1-10> type of crystallographic direction of the crystallites in this component being oriented within a cone of 10° radius of one of the axes of the Cartesian coordinate system,

30% to 70%, by volume, of a second texture component, the second texture component being defined by a {111} crystallographic plane of the crystallites in this component being parallel within +/−10° of the X-Y, X-Z or Z-Y plane of the Cartesian coordinate system and a <−110> type of crystallographic direction of the crystallites in this component being oriented within a cone of 10° radius of one of the axes of the Cartesian coordinate system, and

less than 40%, by volume, of a third texture component, the third texture component being defined by a {100} type of crystallographic plane of the crystallites in this component being parallel within +/−10° of the X-Y, X-Z or Z-Y plane of the Cartesian coordinate system and a <001> type of crystallographic direction of the crystallites in this component being oriented within a cone of 10° of one of the axes of the Cartesian coordinate system.

DETAILED DESCRIPTION

The fan42of the fan section22includes a plurality of circumferentially-spaced airfoils60. The airfoils60can be hollow or solid, and can be made entirely or partially of the aluminum alloy discussed in further detail below. For example, the airfoils60can be fan blades that are rotatable about the central engine axis A, although the examples herein are not limited to rotatable fan blades.FIG. 2illustrates a representative example of one of the airfoils60. The airfoil60includes an airfoil body62that extends at least between leading and trailing edges64a/64b, first and second sides66a/66b, and radially inner and outer ends68a/68b(with respect to the normal orientation of the airfoil60relative to the central engine axis A). Depending on design requirements, the airfoil60can also include other geometric features, such as but not limited to, inner and/or outer platforms and circumferential spacing features.FIG. 2also shows an example coordinate system that can be used to define crystallographic texture components with respect to the airfoil60.

The airfoil body62includes an aluminum alloy that has a controlled crystallographic texture (components volume fraction and sharpness) represented inFIG. 3, with respect to a predefined three-dimensional coordinate system70. A polycrystalline aluminum alloy that has fully random crystalline grain orientations has no crystallographic texture. A “controlled crystallographic texture” refers to at least one selected crystallographic direction being preferentially oriented with respect to the predefined three-dimensional coordinate system70. As used herein, reference to crystallographic directions or planes also refers to all directions and planes that are equivalent by symmetry, as understood in Miller index notation. Example crystallographic texture components in the airfoil60can include 20-100% of the crystallites by volume fraction being aligned according to one of the following examples:

<111> type of crystallographic direction is within 0 to 10 degrees of the Z axis and <110> type of crystallographic direction is within 0 to 10 degrees of X axis and <112> type of crystallographic direction is within 0 to 10 degrees of Y axis.

<111> type of crystallographic direction is within 0 to 10 degrees of the Z axis and <112> type of crystallographic direction is within 0 to 10 degrees of X axis and <110> type of crystallographic direction is within 0 to 10 degrees of Y axis.

<110> type of crystallographic direction is within 0 to 10 degrees of the Z axis and <111> type of crystallographic direction is within 0 to 10 degrees of X axis and <112> type of crystallographic direction is within 0 to 10 degrees of Y axis.

<110> type of crystallographic direction is within 0 to 10 degrees of the Z axis and <112> type of crystallographic direction is within 0 to 10 degrees of X axis and <111> type of crystallographic direction is within 0 to 10 degrees of Y axis.

<112> type of crystallographic direction is within 0 to 10 degrees of the Z axis and <111> type of crystallographic direction is within 0 to 10 degrees of X axis and <110> type of crystallographic direction is within 0 to 10 degrees of Y axis.

<112> type of crystallographic direction is within 0 to 10 degrees of the Z axis and <110> type of crystallographic direction is within 0 to 10 degrees of X axis and <111> type of crystallographic direction is within 0 to 10 degrees of Y axis.

Further, 0 to 40% of the crystallites by volume fraction can be aligned according to one of the following examples:

<100> type of crystallographic direction is within 0 to 10 degrees of the Z axis and <010> type of crystallographic direction is within 0 to 10 degrees of X axis and <001> type of crystallographic direction is within 0 to 10 degrees of Y axis.

<100> type of crystallographic direction is within 0 to 10 degrees of the Z axis and <001> type of crystallographic direction is within 0 to 10 degrees of X axis and <010> type of crystallographic direction is within 0 to 10 degrees of Y axis.

<010> type of crystallographic direction is within 0 to 10 degrees of the Z axis and <001> type of crystallographic direction is within 0 to 10 degrees of X axis and <100> type of crystallographic direction is within 0 to 10 degrees of Y axis.

<010> type of crystallographic direction is within 0 to 10 degrees of the Z axis and <100> type of crystallographic direction is within 0 to 10 degrees of X axis and <001> type of crystallographic direction is within 0 to 10 degrees of Y axis.

<001> type of crystallographic direction is within 0 to 10 degrees of the Z axis and <001> type of crystallographic direction is within 0 to 10 degrees of X axis and <010> type of crystallographic direction is within 0 to 10 degrees of Y axis.

<001> type of crystallographic direction is within 0 to 10 degrees of the Z axis and <010> type of crystallographic direction is within 0 to 10 degrees of X axis and <001> type of crystallographic direction is within 0 to 10 degrees of Y axis.

Further, 0 to 30% of crystallites can be randomly oriented.

An aluminum alloy with crystallographic texture has anisotropic properties. As an example, strength is one anisotropic property, but many other properties will also vary anisotropically. In this regard, the aluminum alloy has one or more high strength directions, which are directions in which the strength of the aluminum alloy is greater than the strength in at least one other direction. For example, the crystallographic directions <111>, <112>, and <110> are high strength directions of aluminum alloys. Thus, by orienting a certain volume fraction of crystallites in one or more of these high strength directions with respect to the predefined three-dimensional coordinate system70, the strength (or other property) of the airfoil60can be tailored to enhance durability and/or performance of the airfoil60.

In the illustrated example, the predefined three-dimensional coordinate system70is a Cartesian coordinate system having orthogonal X-, Y- and Z-axes. For purposes of this disclosure, the Z-axis extends along a radial direction of the airfoil body62, which is perpendicular to the central engine axis A. The X-axis extends in a direction transverse to the first and second sides66a/66b, and the Y-axis extends orthogonally to the Z- and X-axes. In one example, the Y-axis is parallel to the central engine axis A.

A volume fraction of the crystallites can be aligned such that one or more crystallographic directions of the aluminum alloy can be oriented with selected ones of the axes of the Cartesian coordinate system, within a cone (radius) of 10°. For example, as shown inFIG. 3, one or more of the above-described high-strength crystallographic directions is oriented within a cone of 10° radius of one or more of the axes of the three-dimensional coordinate system70. Thus, the airfoil60can exhibit relatively high strength in the radial, axial and transverse directions.

In further examples, the controlled crystallographic texture can also define a texture distribution with respect to volume fractions of one or more different texture components. Such texture components and volume fractions can be determined by X-Ray or electron diffraction analysis, for example. In one example, the texture components distribution includes 20% to 100%, by volume, of a selected, defined texture, such as one of the high strength crystallographic directions.

In another example, the texture distribution includes 30% to 70%, by volume, of a first texture, the first texture component being defined by a {111} type of crystallographic plane being parallel within +/−10° of the X-Y, X-Z or Z-Y plane of the Cartesian coordinate system and a <1-10> type of crystallographic direction being oriented within a cone of 10° of one of the axes of the Cartesian coordinate system.

In a further example, the texture distribution also includes 30% to 70%, by volume, of a second texture, the second texture being defined by a {111} type of crystallographic plane being parallel within +/−10° of the X-Y, X-Z or Z-Y plane of the Cartesian coordinate system and a <−110> type of crystallographic direction being oriented within a cone of 10° of one of the axes of the Cartesian coordinate system. Thus, together, the first and second textures comprise 60% to 100% of the alloy volume.

In a further example of any of the foregoing examples, the texture distribution also includes less than 40%, by volume, of a third texture, the third texture being defined by a {100} type of crystallographic plane being parallel within +/−10° of the X-Y, X-Z or Z-Y plane of the Cartesian coordinate system and a <001> type of crystallographic direction being oriented within a cone radius of 10° of one of the axes of the Cartesian coordinate system.