Dynamic constitutive relation of EMC over a broad range of temperatures and strain rates
In this paper, dynamic properties of EMC were studied sat different temperatures and different strain rates. Firstly EMC was investigated by quasi-static tests. Secondly a series of dynamic compressive experiments of EMC were conducted using the Split Hopkinson Pressure Bar (SHPB) at high strain rates. Corresponding measurements were conducted at temperatures ranging from 20°C to 200°C. The results indicate that the yield strength and flow stress of EMC increase remarkably with the increase of strain rate. However, the yield strength of EMC is almost unchanged with the increase of temperature which is ranging from 20°C to 200°C.
The Impact of Temperature on the Performance of Epoxy Molding Compound
Epoxy molding compound(EMC), one of the largest three kinds of raw materials in semicon-ductor industry, performs the significant functions on the capabilities of discrete and IC. Gelation time and spiral flow length, the basic performance indexes, directly define the process parameters. However, the temperature affects them greatly. The temperature conditions of these procedures, such as manufacture, storage, thawing and molding etc. engender the different extent of impacts. Unapt temperature selected, may lead to the badness of molding workability, encapsulation body defect, and attenuation or fault of the semiconductors capabilities. This paper emphatically expounds the influences of temperature on the usage of EMC and the capabilities of semiconductors.
A New Vacuum Pressure Infiltration CFRP Method and Preparation Experimental Study of Composite
In order to prepare a carbon-fiber-reinforced polymer composite (CFRP) with ideal microstructure and properties, a new vacuum pressure infiltration CFRP method is proposed based on an analysis of existing CFRP preparation process methods. Research on composite material preparation systems was carried out by using this new method principle. The system mainly includes a fiber pre-forming module, a vacuum heating infiltration module, a hot-press curing molding module, and a data acquisition control module. Under the conditions of natural curing at 0 MPa + 6 h + 25 °C, vacuum heating curing at –0.05 MPa + 30 min + 80 °C, and hot-press curing at 0.7 MPa + 5 min + 50 °C, a two-dimensional (2D) CFRP with excellent microstructure and properties was successfully prepared. Observing the microstructure of the prepared composite material, it can be found that the inside of the composite material was sufficiently and uniformly infiltrated, and common preparation defects such as holes and delamination were effectively controlled. Through the performance test, the bending strength of the material reached 790 MPa.