To quantify microstructural characteristics, both morphological and material properties must be characterized. Image processing is a very effective technique for determining morphological characteristics, such as volume fraction, inclusion morphology,[2]​ void,[3]​ and crystal orientations. To make micrographs, optical and electron microscopy are commonly used.

To determine material properties, nanoindentation is a suitable technique for determining properties of elements whose size is in the order of microns and submicrons, for which conventional tests are not feasible. Conventional mechanical tests, such as tensile testing or dynamic mechanical analysis, can only quantify macroscopic properties without any indication of microstructural properties. However, nanoindentation can be used for the determination of local microstructural properties of homogeneous and heterogeneous materials. Microstructures[4]​ can also be characterized by higher order statistical models through which a set of complex statistical properties are extracted from images. In turn, these properties can be used to produce various other stochastic models.[5][6][7]​.

Computer-simulated microstructures, or synthetic microstructures, are generated to replicate the characteristics of real microstructures. They are used to investigate which microstructural characteristic is important for a given property. To ensure statistical equivalence between generated and real microstructures, microstructures are modified after generation to match the statistics of a real microstructure. Such a procedure allows the generation of a theoretically infinite number of computer-simulated microstructures that are statistically equal (have the same statistics) but stochastically different (have different configurations).[3]​[8]​.

A pore in a microstructure, unless desired, is a disadvantage for the properties of the material. In fact, in almost all materials, a pore will be the starting point for the appearance of a breakage, becoming the starting point of a crack. In addition, they are usually quite difficult to remove. The techniques described below involve a high temperature process. However, even those processes can sometimes make the pore even larger. Pores with a large coordination number (surrounded by many particles) tend to grow during thermal processes. This is because the thermal energy becomes a driving force for the growth of the particles that will induce the growth of the pore, since the high coordination number prevents growth towards the pore.

For many materials, it can be seen from their phase diagram that multiple phases can exist at the same time. Those different phases may exhibit a different crystalline structure, thus exhibiting different mechanical properties.[9]​ Furthermore, different phases also exhibit different microstructure (such as grain size and orientation).[10]​ This phenomenon may also improve some mechanical properties, as it may induce crack deflection, which delays the final rupture, as it creates a more tortuous crack path in a thicker microstructure.[11]​.

In some cases, simply changing the way the material is processed can influence its microstructure. An example is the titanium alloy TiAl6V4.[12]​ Its microstructure and mechanical properties are improved by SLM (selective laser melting), which is a 3D printing technique that uses powder and melts the particles with a high-power laser.[13]​ Other conventional techniques to improve the microstructure are thermal processes.[14]​.

These processes are based on the principle that an increase in temperature will induce the reduction or annihilation of pores.[15]​ Hot isostatic pressing (HIP) is a manufacturing process used to reduce the porosity of metals and increase the density of many ceramic materials, thereby improving the mechanical properties and workability of the material.[16]​.

The HIP process exposes the desired material to isostatic gas pressure as well as high temperature in a sealed container (high pressure). The gas must be chemically inert so that no reaction occurs between it and the sample, which is why argon is usually used. Pressure is achieved by simply applying heat to the hermetically sealed container. However, some systems also associate gas pumping with the process to reach the required pressure level. The pressure applied to the materials is equal and comes from all directions (hence the term “isostatic”).[17]​ When castings are treated with HIP, the simultaneous application of heat and pressure eliminates internal voids and microporosity through a combination of plastic deformation, creep, and diffusion bonding; This process improves the fatigue resistance of the component.[18]​.

• - Wikimedia Commons hosts a multimedia category on Microstructure.

To quantify microstructural characteristics, both morphological and material properties must be characterized. Image processing is a very effective technique for determining morphological characteristics, such as volume fraction, inclusion morphology,[2]​ void,[3]​ and crystal orientations. To make micrographs, optical and electron microscopy are commonly used.

To determine material properties, nanoindentation is a suitable technique for determining properties of elements whose size is in the order of microns and submicrons, for which conventional tests are not feasible. Conventional mechanical tests, such as tensile testing or dynamic mechanical analysis, can only quantify macroscopic properties without any indication of microstructural properties. However, nanoindentation can be used for the determination of local microstructural properties of homogeneous and heterogeneous materials. Microstructures[4]​ can also be characterized by higher order statistical models through which a set of complex statistical properties are extracted from images. In turn, these properties can be used to produce various other stochastic models.[5][6][7]​.

Computer-simulated microstructures, or synthetic microstructures, are generated to replicate the characteristics of real microstructures. They are used to investigate which microstructural characteristic is important for a given property. To ensure statistical equivalence between generated and real microstructures, microstructures are modified after generation to match the statistics of a real microstructure. Such a procedure allows the generation of a theoretically infinite number of computer-simulated microstructures that are statistically equal (have the same statistics) but stochastically different (have different configurations).[3]​[8]​.

A pore in a microstructure, unless desired, is a disadvantage for the properties of the material. In fact, in almost all materials, a pore will be the starting point for the appearance of a breakage, becoming the starting point of a crack. In addition, they are usually quite difficult to remove. The techniques described below involve a high temperature process. However, even those processes can sometimes make the pore even larger. Pores with a large coordination number (surrounded by many particles) tend to grow during thermal processes. This is because the thermal energy becomes a driving force for the growth of the particles that will induce the growth of the pore, since the high coordination number prevents growth towards the pore.

For many materials, it can be seen from their phase diagram that multiple phases can exist at the same time. Those different phases may exhibit a different crystalline structure, thus exhibiting different mechanical properties.[9]​ Furthermore, different phases also exhibit different microstructure (such as grain size and orientation).[10]​ This phenomenon may also improve some mechanical properties, as it may induce crack deflection, which delays the final rupture, as it creates a more tortuous crack path in a thicker microstructure.[11]​.

In some cases, simply changing the way the material is processed can influence its microstructure. An example is the titanium alloy TiAl6V4.[12]​ Its microstructure and mechanical properties are improved by SLM (selective laser melting), which is a 3D printing technique that uses powder and melts the particles with a high-power laser.[13]​ Other conventional techniques to improve the microstructure are thermal processes.[14]​.

These processes are based on the principle that an increase in temperature will induce the reduction or annihilation of pores.[15]​ Hot isostatic pressing (HIP) is a manufacturing process used to reduce the porosity of metals and increase the density of many ceramic materials, thereby improving the mechanical properties and workability of the material.[16]​.

The HIP process exposes the desired material to isostatic gas pressure as well as high temperature in a sealed container (high pressure). The gas must be chemically inert so that no reaction occurs between it and the sample, which is why argon is usually used. Pressure is achieved by simply applying heat to the hermetically sealed container. However, some systems also associate gas pumping with the process to reach the required pressure level. The pressure applied to the materials is equal and comes from all directions (hence the term “isostatic”).[17]​ When castings are treated with HIP, the simultaneous application of heat and pressure eliminates internal voids and microporosity through a combination of plastic deformation, creep, and diffusion bonding; This process improves the fatigue resistance of the component.[18]​.

• - Wikimedia Commons hosts a multimedia category on Microstructure.