Jominy Hardenability test Lab Report Example | Topics and Well Written Essays - 1750 words

Jominy Hardenability test - Lab Report Example During testing, water was sprayed on one side of the steel bar when still hot so as to enhance a one-dimensional transfer of heat during cooling. Moving away from the end that was quenched made the temperature rate of change to be altered. The rate of cooling is observed being low as the temperature increases. When the hardness of the surface is measured as a distance function from the end, a profile of hardness was obtained. This profile can be applied to any specimen that is made from steel (Callister 4). Hardenability is, therefore different from hardness as hardness refers to a measure of the extent of resistance for a solid matter towards different types of permanent shapes whenever some amount of force is applied to the solid matter. The macroscopic hardness is hardness with intermolecular bonds that are strong. It occurs whenever the character of the solid matter under force appears to be complex. In this respect, there are a variety hardness measurements. These include indent ation hardness, scratch hardness, and rebound hardness (Bain 3).Comparing the experimental and published hardenability values, it is evidenced that the two pairs of curves are similar to each other. The curves have a similar gradient with just a few differences. These differences were brought about due to experimental errors. Some of the experimental errors came about due to air resistance, parallax, the heterogeneous trait of the calibration plate, faultiness of the Rockwell scale, and wrong calculation.... As widely cited, Hardenability is measured using the measurements of length. It serves the purpose of indicating how deep inside a material of given hardness can be obtained. This is one such vital property in welding and it is inversely proportional to the weldability of a material. This property can be demonstrated in a case where whenever a work piece that is made of steel is quenched; the contact area having water is suddenly cooled and it is often evened out of the given medium. On the contrary, the internal depth of the medium, fails to cool in a rapid in a rapid way and the work pieces inside, cool at a slow rate allowing the austenite to change into a structure besides martensite. The main effect is that the resulting component would be a work piece with different crystal structures, having a hard shell and a core considered being soft and hard for the entire structure. In this case, the softer core is a combination of cementite and ferrite such as the pearlite. In ferrous al loys such as steel, hardenability is a component of the carbon content and other different elements of the alloy. The other alloying elements have relatively important including the calculation using the equivalent material’s carbon content. In quenching, the fluid used facilitates the rate of cooling for the materials as a result of the changing thermal conductivity and specific heat. Components such as water and brine that have the ability to cool faster than oil and air (Callister 9). Apart from this, whenever a fluids are agitated, their rate of cooling is fast. In other cases, the part geometry influences the rate of cooling rate for two samples having different volumes. This means that the material