Polypropylene Laser Welding Material With Needle Fillers
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Laser welding efficiency is reduced in plastic materials containing additives due to energy dispersion and absorption, particularly in those with high crystallinity, which affects the joining process and mechanical properties.
Innovation Solution
A joining material comprising a polypropylene resin with a specific melt index and needle-shaped inorganic fillers with a controlled aspect ratio, dispersed within a polymer matrix to enhance mechanical properties and minimize energy dispersion during laser welding.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If additives such as organic and inorganic fillers are included in plastic materials to reinforce physical properties, then mechanical strength is improved, but laser welding efficiency is reduced due to energy dispersion and absorption
Solution Approach 1:
The patent changes the physical and chemical parameters of the filler particles by controlling their size distribution (D10, D50, D90 values) and aspect ratio (10:1 to 20:1). This optimization allows the fillers to reinforce mechanical properties while minimizing their negative impact on laser energy transmission, thereby maintaining both strength and welding efficiency
Solution Approach 2:
The patent uses a composite material system consisting of polypropylene resin as the matrix and needle-shaped inorganic fillers as reinforcement. This composite structure allows the material to simultaneously achieve enhanced mechanical strength from the fillers and acceptable laser welding efficiency from the polymer matrix
2Strength
If plastic materials with high crystallinity are used to improve mechanical properties, then strength is enhanced, but laser welding efficiency is reduced due to energy scattering and absorption
Solution Approach 1:
The patent optimizes the crystallinity parameter of the polypropylene resin within a specific range (30% to 70%) to balance mechanical strength and laser transmission. This controlled crystallinity ensures adequate structural strength while preventing excessive energy scattering during laser welding
3Strength
If needle-shaped inorganic fillers with high aspect ratio are added to improve mechanical properties, then flexural modulus is enhanced, but energy dispersion during laser transmission increases
Solution Approach 1:
The patent precisely controls the aspect ratio of needle-shaped inorganic fillers within the range of 10:1 to 20:1, and optimizes the particle size distribution (D10: 2-5 μm, D50: 5-10 μm, D90: 10-20 μm). This parameter optimization achieves the desired flexural modulus while minimizing energy dispersion during laser transmission
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 solution achieves improved mechanical strength, flexural modulus, and joining efficiency by effectively transmitting laser energy, resulting in a high-strength laser joined body suitable for various applications.
Implementation Method 1
irradiating laser to form a welding region in a region where the joining material for laser welding and the material to be joined are laminated, wherein the laser is irradiated to pass through the joining material for laser welding toward a surface of the material to be joined
Data Source
AI summary
A joining material for laser welding, a laser welding method using the same, and a laser joined body using the laser welding method. The joining material includes a polymer matrix and a needle-shaped inorganic filler. The polymer matrix includes a polypropylene resin having a melt index of 80 g/10 min or more to 95 g/10 min or less as measured at a temperature of 230° C. and a load of 2.16 kg, and the needle-shaped inorganic filler has an aspect ratio of 10:1 to 20:1.