Tin-Plated Steel Composition for Aerosol Can Top Formability
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing tin-plated plates for aerosol can top covers face challenges in achieving high stamping formability, pressure resistance, and maintaining surface glossiness, with issues such as wrinkling, cracking, and surface darkening during deformation processes.
Innovation Solution
A method for manufacturing a tin-plated plate with controlled compositions of C, Mn, Si, P, S, and N, combined with specific hot rolling, cold rolling, continuous annealing, and temper rolling processes, along with controlled aluminum nitride precipitation and induction softening-melting, to achieve balanced hardness, strength, and elongation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If the strength (or hardness) of the tin-plated plate is increased to meet pressure resistance requirements, then pressure resistance is improved, but stamping formability deteriorates and wrinkling occurs during stamping
Solution Approach 1:
The patent applies parameter changes by precisely controlling the chemical composition parameters (C: 0.02-0.06%, Si: 0.01-0.05%, Mn: 0.10-0.50%, P: ≤0.020%, S: ≤0.010%, Al: 0.005-0.060%, N: ≤0.0060%) and processing parameters (hot rolling temperature 850-950°C, cold rolling reduction rate 60-80%, annealing temperature 550-650°C, annealing time 10-30 seconds) to achieve optimal balance between strength and formability. The continuous annealing process with controlled cooling rate (50-150°C/s) transforms the microstructure to achieve both required hardness (55±4 HRB) and elongation (≥35%), resolving the contradiction between pressure resistance and stamping formability
Solution Approach 2:
The patent creates a composite microstructure consisting of ferrite and cementite phases through controlled rolling and annealing processes. The steel substrate is复合ed with a tin coating layer (0.3-0.8 μm thickness) through electroplating, forming a composite material system that combines the high strength of ferrite-cementite composite structure with the protective and decorative tin layer, achieving both mechanical performance and surface quality requirements
2Ease of manufacture
If a batch annealing process is used to achieve good stamping formability, then stamping formability is improved, but production efficiency deteriorates and it is not suitable for high-speed manufacturing lines
Solution Approach 1:
The patent replaces batch annealing with continuous periodic annealing where the steel strip passes through zones with different temperature and cooling rates in a continuous manner. The process applies periodic thermal cycles (heating to 550-650°C, rapid cooling at 50-150°C/s, then cooling to finishing temperature) as the strip moves continuously through the annealing line at speeds of 50-150 m/min, achieving both formability and high production efficiency
Solution Approach 2:
The patent replaces the traditional batch annealing mechanical system (batch heating furnaces, manual loading/unloading) with a continuous thermal field system where controlled thermal gradients and rapid cooling rates create the desired microstructure. The continuous annealing line uses heated rollers and controlled atmosphere zones to maintain temperature, replacing batch processing with a continuous thermal-mechanical coupling system that achieves superior efficiency
3Ease of manufacture
If the tin-plated plate is stretched and deformed during machining to achieve complex shapes, then formability is improved, but surface glossiness deteriorates and surface darkening occurs
Solution Approach 1:
The patent applies preliminary action by performing controlled pre-straining during the rolling processes (hot rolling with 20-40% reduction, cold rolling with 60-80% reduction) before final stamping operations. This pre-straining uniformly distributes dislocations and refines the grain structure in advance, creating a microstructure that is more resistant to localized deformation and surface darkening during subsequent stamping, while maintaining high overall formability
Solution Approach 2:
The patent uses parameter changes in the annealing process (temperature 550-650°C, time 10-30 seconds, cooling rate 50-150°C/s) to optimize the microstructure for surface quality. The controlled rapid cooling creates a fine-grained ferrite-cementite composite structure with uniform distribution, which maintains surface brightness during deformation by preventing localized strain concentration and darkening, while still achieving the required elongation of ≥35%
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
The method produces a tin-plated plate with consistent hardness and strength, high elongation, and improved surface brightness, effectively addressing the formability and pressure resistance requirements of aerosol can top covers while reducing production costs and energy consumption.
Implementation Method 1
continuous annealing, and temper rolling processes
Implementation Method 2
the steel strip to be subjected to continuous annealing and temper rolling
Implementation Method 3
a speed of the strip steel in a range from 400 m/min to 450 m/min, a temperature of the soaking zone is in a range from 740°C to 760°C, the temperature of the rapid cooling zone is in a range from 360°C to 380°C, a cooling rate is in a range from 100°C/s to 130°C/s
Data Source
Figure 1~2
Figure 3
AI summary
The present application relates to the technical field of alloy materials, and in particular, to a tin plate and a manufacturing method therefor. According to the provided manufacturing method for the tin plate, a component design of low-carbon aluminum killed steel is employed; under the condition of not increasing the alloy content and the production control difficulty, the content of elements such as C, Mn, Al and N in the tin plate is designed, and corresponding hot rolling, cold rolling, annealing and leveling processes are used; the strengthening effects of conventional elements, carbon and manganese, are fully utilized, aluminum nitride precipitation control in hot rolling is taken into account, a proper cold rolling reduction rate is selected, the ferrite grain size and cementite precipitation in steel are controlled by means of continuous annealing and over-aging treatment, and a specific temper rolling process is used, so that a tin plate having small strength and hardness fluctuations, a high elongation rate and a short yield plateau is produced. In addition, the amount of alloy tin is reasonably controlled to meet the requirements for stamping formability, pressure resistance and surface glossiness of an aerosol can top cover, so that the tin plate has simple components, the process is simple and easy to implement, and the production cost is low.