Which two factors greatly affect the suitability of target material in an X-ray tube?

The suitability of target material in an X-ray tube is primarily influenced by its atomic number and melting point. The atomic number is crucial because it determines the material's ability to absorb and generate X-rays. A higher atomic number results in greater X-ray production and better energy resolution, making materials like tungsten, which has a high atomic number, excellent targets.

The melting point is equally important because the target material must withstand the intense heat generated during the X-ray production process without deforming or melting. High melting point materials maintain their structural integrity, ensuring consistent performance and longevity of the X-ray tube.

Together, these two factors—atomic number and melting point—ensure optimal X-ray generation and durability of the target material under operational conditions, making them the primary considerations for suitability in an X-ray tube.