Laser Cladding Measurement for Thermal Distortion Compensation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Laser mandrel welding processes face inaccuracies leading to significant tolerances, heat expansion issues due to high temperatures, and rapid cooling of materials, resulting in unacceptable dimensional changes in workpieces, which complicates precise production and repair of workpieces.
Innovation Solution
A machine tool equipped with a machine control system, temperature sensors, and an order welding head that allows for precise control of thermal conditions through automatic tool change mechanisms and data logging, enabling better prediction and management of thermal effects during production.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If laser cladding welding is used to manufacture workpieces, then productivity is improved through automated material deposition, but manufacturing precision deteriorates due to thermal expansion and rapid cooling causing dimensional changes of 1 mm or more
Solution Approach 1:
The patent applies preliminary action by measuring the workpiece geometry before laser cladding welding begins, storing this initial state data, and using it as a reference for subsequent compensation calculations. This pre-measurement allows the system to anticipate and correct for thermal expansion and cooling contraction that will occur during the welding process, thereby maintaining manufacturing precision while enabling high-speed automated deposition.
Solution Approach 2:
The patent implements feedback through continuous measurement of the workpiece geometry during and after the laser cladding process. The measuring device captures real-time dimensional changes, and this measurement data is fed back to the control system, which automatically adjusts welding parameters and deposition paths to compensate for thermal effects. This closed-loop feedback mechanism enables the system to maintain dimensional accuracy despite the high productivity of automated material deposition.
2Productivity
If high laser power is used for welding, then productivity is improved through faster material deposition, but temperature increases causing thermal expansion and dimensional inaccuracies
Solution Approach 1:
The patent applies dynamics by making the laser power dynamically adjustable rather than fixed. The control system continuously monitors workpiece temperature and automatically modulates the laser power output in real-time based on thermal conditions. This dynamic adjustment allows the system to maintain high deposition speeds when thermal conditions permit while reducing power when temperature thresholds are approached, thereby balancing productivity with temperature control.
Solution Approach 2:
The patent implements parameter changes by varying multiple welding parameters including laser power, deposition rate, and travel speed based on real-time temperature measurements. When temperature increases are detected, the system automatically adjusts these parameters to reduce heat input while maintaining acceptable productivity. This multi-parameter adjustment strategy enables the system to optimize the balance between material deposition speed and workpiece temperature control.
3Productivity
If material is rapidly deposited through laser cladding, then productivity is improved, but the material cools quickly causing dimensional changes and requiring post-processing
Solution Approach 1:
The patent applies preliminary action by measuring and recording the workpiece geometry immediately before material deposition begins. This initial geometric state is stored and used as a reference for calculating compensation values. By having this baseline measurement ready in advance, the system can quickly compensate for dimensional changes caused by rapid cooling after high-speed deposition, thereby maintaining manufacturing precision without sacrificing productivity.
Solution Approach 2:
The patent implements feedback by continuously measuring the workpiece geometry after material deposition and comparing it against the target dimensions. The measurement data is fed back to the control system, which calculates the deviations caused by rapid cooling and automatically generates compensation paths for subsequent welding operations. This real-time feedback loop enables the system to maintain dimensional stability even when operating at high deposition rates that cause rapid material cooling.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This solution enables precise production of workpieces by predicting and managing thermal conditions, reducing dimensional inaccuracies and ensuring consistent quality by creating a meaningful manufacturing protocol that accounts for temperature variations.
Implementation Method 1
a welding head (20) that can be inserted into the tool holder (14), wherein the welding head (20) has a laser beam for cladding welding
Implementation Method 2
a measuring device (23) for measuring position and/or geometry of the workpiece (100)
Implementation Method 3
temperature sensors
Implementation Method 4
The coefficient of thermal expansion of iron is 10−5 /°C. A temperature gradient of, for example, 300°C between the manufacturing temperature (approximately above 300°C) and the operating temperature (approximately room temperature) leads to a dimensional change of 3 × 10−3 or 3‰
Data Source
Figure 1~2
Figure 3~4a
Figure 4b~5
AI summary
A measuring device for measuring a workpiece in a cladding welding machine has a position measuring device for determining position data, preferably in three dimensions, of surface points of a workpiece, a temperature measuring device for determining temperature data relating to the temperature at a surface point in close proximity to the measurement of the point with the position measuring device, and a storage device for storing position and temperature data of several surface points in a manner that can be assigned to each other.