Looking for breakthrough ideas for innovation challenges? Try Patsnap Eureka!

Adding control method for silicon content of nodular cast iron, casting method of nodular cast iron and casting

A technology of ductile cast iron and control method, which is applied in the field of metallurgy and cast iron alloys, can solve the problem that the tensile strength and notched impact toughness of ductile iron cannot be balanced, and achieve the effect of high tensile strength and elongation

Active Publication Date: 2019-11-22
TIANRUN IND TECH CO LTD +1
View PDF4 Cites 1 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0006] The second object of the present invention is to provide a casting method of ductile iron, which solves the problem that the tensile strength and notched impact toughness of ductile iron cannot be balanced

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0065] A method for preparing nodular cast iron for connecting rods with high tensile strength and high notched impact toughness, comprising the following steps:

[0066] The leftovers of automobile stamping parts are used as raw materials and melted in a 7.5-ton electric furnace. During the melting process, a mixture of microcrystalline graphite powder and silicon carbide crystals is added to promote the precipitation of carbon in the form of graphite, and at the same time play a role in increasing silicon, and then carry out alloying treatment, spheroidization treatment and casting molding. The rod blank is subjected to secondary isothermal normalizing and tempering treatment.

[0067] In this embodiment, scraps of automobile stamping parts are used as raw materials, and the ingredient list is compiled and input into the automatic ingredient weighing system for automatic weighing.

[0068] Add 7 tons of automobile stamping parts scraps to the electric furnace, then add 350 ...

Embodiment 2

[0080] A method for preparing nodular cast iron for connecting rods with high tensile strength and high notched impact toughness, comprising the following steps:

[0081] (1) Use the scraps of automobile stamping parts as raw materials, compile the ingredient list and input it into the automatic ingredient weighing system for automatic weighing.

[0082] Add 7 tons of automobile stamping parts scraps to the electric furnace, then add 350 kg of microcrystalline graphite powder and silicon carbide crystal mixture, and start melting.

[0083] (2) Add copper alloy and make the copper equivalent in molten iron be 0.8%, specifically include:

[0084] Sampling and analysis of the original alloy element content (wt%) in molten iron after molten iron melting: Mn 0.63, Cr 0.162, Mo0.092, Ni 0.037, Sn 0.0018, Cu 0.036, V 0.0078, detection of phosphorus content in molten iron 0.032%, sulfur Content 0.015%, silicon content 1.08%. Get 0.8% of copper equivalent, and calculate the copper co...

Embodiment 3

[0094] A method for preparing nodular cast iron for connecting rods with high tensile strength and high notched impact toughness, comprising the following steps:

[0095] (1) Use the scraps of automobile stamping parts as raw materials, compile the ingredient list and input it into the automatic ingredient weighing system for automatic weighing.

[0096] Add 7 tons of automobile stamping parts scraps to the electric furnace, then add 350 kg of microcrystalline graphite powder and silicon carbide crystal mixture, and start melting.

[0097] (2) Add copper alloy and make the copper equivalent in molten iron be 1.0%, specifically include:

[0098] Sampling and analysis of the original alloy element content (wt%) in molten iron after melting: Mn 0.52, Cr 0.225, Mo0.165, Ni 0.032, Sn 0.00187, Cu 0.026, V 0.018, detection of phosphorus content in molten iron 0.035%, sulfur Content 0.011%, silicon content 1.12%. Take 1.0% of copper equivalent, and calculate the copper content that ...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

PropertyMeasurementUnit
tensile strengthaaaaaaaaaa
tensile strengthaaaaaaaaaa
elongationaaaaaaaaaa
Login to View More

Abstract

The invention provides an adding control method for silicon content of nodular cast iron, a casting method of the nodular cast iron and a casting and relates to the technical field of metallurgy and cast-iron alloys. The adding control method for the silicon content of the nodular cast iron comprises the following steps: smelting the nodular cast iron by taking scrap steel as a raw material; and after molten iron is melted, first adding a copper alloy and enabling the copper equivalent in the molten iron to be 0.8 to 1.0 percent, wherein a control formula of the copper equivalent is shown as (II), and then adding silicon iron and enabling the content of silicon added in the molten iron to meet the condition of a formula (I). According to the adding control method, by dynamically regulatingthe silicon content, the problems that the nodular cast iron has high tensile strength but low notch impact toughness, or has high notch impact toughness but low tensile strength are solved. The casing body obtained by the method has the characteristics that the tensile strength is greater than or equal to 900 MPa, the elongation rate is greater than or equal to 7 percent, and the normal temperature notch impact work is greater than or equal to 7 J; and the casting can be applied to the production of connecting rods.

Description

technical field [0001] The invention relates to the technical field of metallurgy and cast iron alloys, in particular to a method for controlling the addition of silicon in ductile iron, a casting method of ductile iron and castings. Background technique [0002] Ductile iron (referred to as ductile iron) has poor impact toughness, especially notched impact toughness. Existing ductile iron generally does not require impact toughness except for ferrite ductile iron. Even if impact energy needs to be tested, it is limited to the impact energy of unnotched test blocks. Although the notched impact energy of ferritic ductile iron is high, its tensile strength is low. For example, the national standard GB / T1348 is QT400-18R, and its notched impact energy at room temperature is ≥14J, but its tensile strength is only above 400MPa; Pearlitic ductile iron QT900-2 with high strength, although the tensile strength can reach more than 900MPa, the notched impact energy at room temperatur...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
Patent Type & Authority Applications(China)
IPC IPC(8): C21C1/10C22C33/08C21D1/28C21D5/00C22C37/10C22C37/08C22C37/04
CPCC21C1/10C22C33/08C21D1/28C21D5/00C22C37/10C22C37/08C22C37/04C21D2211/009C21D2211/005Y02P10/20C21D5/14C21D1/32C21C1/105
Inventor 丛建臣邵诗波于海明戴学忠倪培相冯梅珍吕世杰丛红日
Owner TIANRUN IND TECH CO LTD
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Patsnap Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Patsnap Eureka Blog
Learn More
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic, Popular Technical Reports.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap|About US| Contact US: help@patsnap.com