KT Metal Castings Blogs

Non-expendable mold casting uses reusable molds that can produce hundreds or thousands of parts before wearing out. Unlike single-use molds, these durable molds save time and money in high-volume production. What Is Non-expendable Mold Casting Non-expendable mold casting is a metal casting process that uses reusable molds to create metal…

Expandable (expendable) casting uses single-use molds that are broken or destroyed to remove the casting, whereas non-expandable (permanent) casting uses durable molds that can be reused for many parts. In expendable processes (also called expendable-mold casting), the mold is usually made from sand, plaster, wax or ceramic and is sacrificed…

Heat treatment is a critical post-casting step to refine the microstructure and mechanical properties of metal components. By carefully heating a casting to specific temperatures, holding (soaking) for controlled times, and cooling in defined ways, foundries can tailor hardness, strength, ductility, toughness, wear resistance, and residual stress. Typical heat treatments…

Investment casting creates metal parts with excellent surface finish and tight tolerances. To get the best results, you need to follow specific design rules. Wall Thickness Wall thickness is one of the most critical factors in investment casting design. You can achieve walls as thin as 0.75 mm (0.030 inches)…

Gas porosity is a defect where dissolved gases create bubbles that get trapped as metal solidifies during the casting process. When metal is molten, it can hold much more gas than when it’s solid. As the metal cools, excess gas forms bubbles that become permanent voids in the final casting.…

Shrinkage cavity and gas porosity are two distinct types of casting defects that occur during metal solidification. Shrinkage creates jagged voids when cooling metal contracts, while gas porosity forms smooth, round bubbles from trapped gases. What is Shrinkage Defects Shrinkage defects are cavities that form when molten metal contracts during…

Porosity defects are unwanted holes or cavities that form in metal castings, making parts weaker and more likely to fail. In investment casting, porosity is one of the most common problems manufacturers face. There are three main types of porosity: gas porosity (smooth, round bubbles), shrinkage porosity (jagged, tree-like cavities),…

The main difference between investment casting and CNC machining is how the material is shaped. Investment casting creates parts by pouring molten metal into wax-based molds, ideal for complex geometries. CNC machining cuts material from a solid block, offering higher precision, faster turnaround, and better suitability for tight tolerances. What…

Shrinkage in metal casting describes internal cavities or surface sink marks that form because molten metal contracts by roughly 1–6 % during solidification. Without properly placed risers to supply extra liquid metal, the solidifying metal cannot fill the volume loss, leaving voids that weaken the finished part. What Is Shrinkage…

The most common defects in investment casting include shrinkage, porosity, misruns, cold shuts, and inclusions. Shrinkage is caused by improper solidification; porosity results from trapped gas; misruns and cold shuts stem from low metal temperatures; inclusions occur due to ceramic shell breakdown or contamination. Cavity-Type Defects Gas Porosity Gas porosity…