Filled and unfilled temperature-dependent epoxy resin blends for lossy transducer substrates.
Filled and unfilled temperature-dependent epoxy resin blends for lossy transducer substrates.
复制标题
用于有损耗传感器基板的填充和未填充的温度依赖性环氧树脂混合物。
DOI：
10.1109/tuffc.2009.1110
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发表时间：
2009
期刊：
影响因子：
--
通讯作者：
Hossack,JohnA
中科院分区：
文献类型：
--
作者：
Eames,MatthewDC;Hossack,JohnA
In the context of our ongoing investigation of low-cost 2-dimensional (2-D) arrays, we studied the temperature- dependent acoustic properties of epoxy blends that could serve as an acoustically lossy backing material in compact 2-D array-based devices. This material should be capable of being machined during array manufacture, while also providing adequate signal attenuation to mitigate backing block reverberation artifacts. The acoustic impedance and attenuation of 5 unfilled epoxy blends and 2 filled epoxy blends - tungsten and fiberglass fillers - were analyzed across a 35degC temperature range in 5degC increments. Unfilled epoxy materials possessed an approximately linear variation of impedance and sigmoidal variation of attenuation properties over the range of temperatures of interest. An intermediate epoxy blend was fitted to a quadratic trend line with R2values of 0.94 and 0.99 for attenuation and impedance, respectively. It was observed that a fiberglass filler induces a strong quadratic trend in the impedance data with temperature, which results in increased error in the characterization of attenuation and impedance. The tungsten-filled epoxy was not susceptible to such problems because a different method of fabrication was required. At body temperature, the tungsten-filled epoxy could provide a 44 dB attenuation of the round-trip backing block echo in our application, in which the center frequency is 5 MHz and the backing material is 1.1 mm thick. This is an 11 dB increase in attenuation compared with the fiberglass-filled epoxy in the context of our application. This work provides motivation for exploring the use of custom-made tungsten-filled epoxy materials as a substitute PCB-based substrate to provide electrical signal interconnect.
