Amorphous Ni-Based Brazing Foil for Long Uniform Joint Seams
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing nickel-based brazing foils face challenges in producing reliable, cost-effective joints with uniform geometry over long lengths due to geometrical variations and the formation of hard phases during rapid solidification, leading to short foil lengths and inadequate corrosion resistance.
Innovation Solution
A nickel-based brazing foil composition with specific atomic percentages of Ni, Cr, B, P, and optional elements like Mo, Nb, Ta, W, Cu, Fe, and Co, subjected to rapid solidification on a moving cooling surface, resulting in an amorphous, ductile foil with suppressed hard phase formation and improved corrosion resistance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If rapid solidification process is used to produce ductile amorphous brazing foil, then ductility and reliability of joints are improved, but geometrical variations occur leading to short foil lengths
Solution Approach 1:
The patent modifies the chemical composition parameters of the brazing alloy by adding specific amounts of silicon (0.1-5 wt%), boron (0.1-5 wt%), and phosphorus (0.1-5 wt%) to the nickel-chromium base alloy. These parameter changes in composition suppress hard phase formation during rapid solidification, enabling production of longer amorphous foil lengths while maintaining ductility and joint reliability
Solution Approach 2:
The patent creates a composite alloy system combining nickel, chromium, and glass-forming elements (silicon, boron, phosphorus). This composite material composition promotes amorphous structure formation during rapid solidification while suppressing crystalline hard phases, thereby extending foil length without sacrificing reliability
2Object-affected harmful factors
If conventional Ni-Cr braze alloy is used, then corrosion resistance is achieved, but production costs are high and foil geometry varies
Solution Approach 1:
The patent optimizes the chromium content parameter to a specific range (5-20 wt%) and introduces controlled amounts of silicon, boron, and phosphorus. This parameter optimization maintains adequate corrosion resistance while reducing production costs by minimizing expensive chromium content and eliminating the need for costly post-processing to correct geometrical variations
3Temperature
If glass-forming elements are added to reduce melting temperature, then processing temperature is reduced, but hard phases form during solidification
Solution Approach 1:
The patent carefully controls the composition parameters of glass-forming elements, specifically maintaining silicon at 0.1-5 wt%, boron at 0.1-5 wt%, and phosphorus at 0.1-5 wt%. This precise parameter control enables the alloy to form amorphous structure during rapid solidification, suppressing crystalline hard phase formation while maintaining reduced processing temperatures
Solution Approach 2:
The patent develops a composite alloy system where nickel-chromium base is combined with multiple glass-forming elements (Si, B, P) in specific proportions. This composite composition promotes amorphous phase formation during solidification, preventing hard crystalline phases from forming even at reduced processing temperatures
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 enables the production of continuous foil lengths with small geometric variations and enhanced corrosion resistance, reducing production costs and ensuring reliable solder seams, suitable for applications requiring high mechanical stability and corrosion resistance.
Implementation Method 1
a molten mass consisting essentially of NirestCraBbPcSid is rapidly solidified on a moving cooling surface with a cooling speed of more than approximately 105° C./sec to produce an amorphous brazing foil
Implementation Method 2
heating the solder joint to a temperature above the liquidus temperature of the brazing foil to form a heated solder joint
Implementation Method 3
cooling of the heated solder joint to form a cooled solder joint between the parts to be joined
Data Source
AI summary
A process for producing an amorphous ductile brazing foil is provided. According to one example embodiment, the method includes providing a molten mass, and rapidly solidifying the molten mass on a moving cooling surface with a cooling speed of more than approximately 105° C./sec to produce an amorphous ductile brazing foil. A process for joining two or more parts is also provided. The process includes inserting a brazing foil between two or more parts to be joined, wherein the parts to be joined have a higher melting temperature than that the brazing foil to form a solder joint and the brazing foil comprises an amorphous, ductile Ni-based brazing foil; heating the solder joint to a temperature above the liquidus temperature of the brazing foil to form a heated solder joint; and cooling the heated solder joint, thereby forming a brazed joint between the parts to be joined.