The ability of a material to conduct heat is primarily determined by its thermal conductivity. When an element sample is hammered into a sheet, its thermal conductivity can be affected by several factors:

1. Increased Surface Area: Hammering the sample into a sheet increases its surface area. This means that there are more surface atoms available to transfer heat, potentially leading to improved heat conduction.

2. Crystal Structure Changes: The hammering process can introduce defects and changes in the crystal structure of the material. These changes can disrupt the orderly arrangement of atoms and hinder the efficient transfer of heat, potentially reducing thermal conductivity.

3. Density Changes: Hammering can cause the sample to become denser, which can impact its thermal conductivity. Denser materials tend to conduct heat better than less dense materials because the atoms are packed more closely, facilitating the transfer of heat energy.

4. Impurities and Defects: The hammering process may introduce impurities or create defects in the material, which can act as barriers to heat flow and reduce thermal conductivity.

Overall, the effect of hammering an element sample into a sheet on its heat conduction properties can vary depending on the specific material, the extent of hammering, and the resulting changes in its physical properties. Some materials may experience improved thermal conductivity, while others may exhibit decreased conductivity due to structural changes or the introduction of defects.