For semiconductor and laser micro-processing equipment, a hidden problem troubles many precision structural parts: residual internal stress releases gradually after machining and causes slow deformation of reference surfaces. This leads to axis offset and optical drift, damaging positioning accuracy and production yield. For nano-scale instruments, even deformation of hundreds of nanometers can impair equipment performance. UNPARALLELED Group's zero-stress nano-grade granite components are designed to eliminate such risks. After precision finishing, these parts maintain stable geometry and will not deform spontaneously over time.
Metal workpieces commonly retain residual stress after cutting, which slowly releases and causes warping. Granite does not creep, but cutting and rough grinding introduce local near-surface stress. Without stress relief, even parts passing final inspection may slowly deform under storage or working loads, which is the main cause of precision decay for ordinary granite parts.
Zero-stress treatment is a gradual aging process. UNPARALLELED performs long-duration stress aging on granite blanks right after rough cutting to release original stress from quarrying and cutting. A second stabilization process follows semi-finish grinding to remove machining-induced surface stress. The whole procedure avoids sharp temperature changes that introduce new stress. When entering nano-precision fine grinding, the blank already reaches a balanced stress state.
At the final finishing stage, newly generated machining stress is minimized. After grinding, the internal stress field is balanced, and residual stress falls below the threshold that triggers measurable shape change. "Zero-stress" does not mean absolute zero stress; it means residual stress is too low to cause spontaneous deformation. The finished granite component retains its contour, flatness and hole position accuracy for a long time under normal ambient conditions.
This stability is highly valuable for equipment running continuously. Femtosecond laser and semiconductor inspection systems often operate nonstop for years with slight temperature variation and cyclic dynamic loads. Ordinary structures slowly deform under combined stress release and load, while UNPARALLELED zero-stress granite keeps its datum unchanged, supporting linear motors, air-bearing slides and optical assemblies.
Zero-stress does not equal immunity to all deformation. Severe impact, improper support, local overload or extreme thermal shock can still cause mechanical deflection or chipping. What this technology prevents is spontaneous deformation from slow stress release, namely time-dependent shape change without external force under normal working conditions.
Stabilized workpieces are measured repeatedly in constant-temperature vibration-isolated metrology labs. Repeated flatness and geometric tolerance tests over time confirm no precision drift. Only parts verified free from spontaneous deformation trend are approved for cleaning and packaging.
Zero-stress nano-grade granite components eliminate the source of time-dependent shape change by removing residual stress. With systematic stress stabilization technology, UNPARALLELED granite maintains consistent geometry after finishing, delivering long-term reliable datum for semiconductor and ultra-precision laser equipment and reducing maintenance cost.