Process variable

About: Process variable is a research topic. Over the lifetime, 3983 publications have been published within this topic receiving 43130 citations. The topic is also known as: process parameter.

Process and device for automatic determination of parameters for process control systems with unknown transfer behaviour, in particular for process control systems for resistance spot welding.

Abstract: A process and a device for automatic determination of parameters for process control systems with unknown transfer behavior are useful for controlling special technical processes in which a functional relationship between process input and process output variables is unknown, at least in parts, while maintaining the properties of the output variables (target functions) within certain acceptable limits. To this end, measured values obtained by the process are subjected to statistical analysis from which control parameters such as theoretical value functions and weighting factors are derived automatically and incorporated in a universally applicable control specification. The control specification is used to determine the control parameter. Adaptation to different processes as well as suitability tests for various control parameters for process control can be carried out comparatively simply using predetermined calculation procedures, conversion factors or the like.

Method and system for deposition tuning in an epitaxial film growth apparatus

Abstract: A method of calculating a process parameter for a deposition of an epitaxial layer on a substrate. The method includes the steps of measuring an effect of the process parameter on a thickness of the epitaxial layer to determine a gain curve for the process parameter, and calculating, using the gain curve, a value for the process parameter to achieve a target thickness of the epitaxial layer. The value is calculated to minimize deviations from the target thickness in the layer. Also, a substrate processing system comprising that includes a processor to calculate a value for the process parameter to achieve a substantially uniform epitaxial layer of a target thickness on the substrate, where the value is calculated using a gain curve derived from measurements of layer uniformity as a function of the value of the process parameter.

Optimization of process parameters for friction stir welding of joining A6061 and A6082 alloys by Taguchi method

Abstract: The friction stir welding is a pioneering solid-state metal joining technique for producing high-quality joints in materials. In this article, Taguchi approach is applied to analyze the optimal process parameters for optimum tensile strength and hardness of welded dissimilar A6061 and A6082 alloys. An orthogonal array of L9 is implemented and the analysis of variance is employed to investigate the importance of parameters on responses. The experimental tests, conducted according to combination of rotational speed, tool tilt and types of tool pin profile parameters. The results indicate that the rotational speed is most significant process parameter that has the highest influence on tensile strength and hardness, followed by tool pin profile and tool tilt. The optimum results verified by conducting confirmation experiments. The predicted optimal value of tensile strength and hardness of dissimilar joints produced by friction stir welding are 267.74 MPa and 80.55 HRB, respectively.

Process variable gauge interface and methods regarding same

Abstract: A graphical user interface for providing real-time process information to a user with regard to a process that is operable under control of one or more process variables includes a scale extending along a gauge axis and one or more bars extending along the gauge axis. Each bar is representative of a set of high and low process limit values for a process variable. Further, the graphical user interface includes a graphical shape displayed along the gauge axis representative of a current value of the process variable. A computer implemented method for providing the graphical user interface is also provided.

Friction surfacing of Ti–6Al–4V: Process characteristics and deposition behaviour at various rotational speeds

Abstract: By the process of friction surfacing, coatings are generated from metallic materials at temperatures below their melting range. The high degree of deformation while depositing leads to grain refinement in the microstructure, which has a positive effect on the mechanical properties of the layer. The applicability of the process has been described for a large number of materials. The deposition of Ti–6Al–4V has been reported in one publication but was not systematically studied. Therefore, the main aims of the present work are to define the process parameter fields for the deposition of Ti–6Al–4V leading to flash and defect free coatings and associate them with geometric features of the deposited layer. This investigation has shown that Ti–6Al–4V coatings can be effectively deposited onto a Ti–6Al–4V substrate by friction surfacing. A wide range of process parameters was established in which coatings of high quality have been obtained. The consumption rate control has been implemented as an efficient mode for the deposition of Ti–6Al–4V coatings. Temperature measurements at the coating interface have been accomplished showing that the coating material has been deformed in the β-phase. Furthermore, the homogeneity of the coating surface has been established to be a function of the rotational speed. The coatings exhibited a defect-free bond at the interface with the substrate. Two process parameter ranges with respect to the flash formation have been established. One of them enables flash-free coatings and the other generates coatings with flash formation on the retreating side, which can be controlled by the rotational and deposition speeds. Moreover, an increase in the rotational speed has been shown to lead to an increase in the coating thickness and width as well as an increase in the deposition efficiency up to 39 %.