Buying ultrasonic transducer

Hello.
Is there any qebsite that I could buy ultrasonic transducer?
I find 1.5mhz (or it will find 1.4 or 1.6) long bandwidth frequency transducer.
Or is it possible to make transducer with piezo crystal?

A quick Google search turned up several different websites.

Probably the other usual suspects such as Amazon, Aliexpress, Taobao, Element14, Mouser, Digikey etc. also have such transducers.

So what's your problem, really?

Here is an example of an ultrasonic transducer

But your frequency range around 1.5MHz is well above the ultrasonic range and is well into the radio frequency spectrum.

Maybe say a bit more about what you are intending to do.

could I make ultrasound transducer?
Is it just piezo crystal and pulse Voltage, so If I prepare piezo crystal and soldering up and down part,
then give pulse signal, Is it a ultrasound transducer?

Make an ultrasonic transducer ? I'm not sure about that. Maybe some one else can answer. However, at less than a dollar for a ready made one, personally, I'd buy one.
I guess that you can use the arduino tone() function to generate signals in at least the low ultrasonic range to feed into the transducer.

dongjee33:
Hello.
Is there any qebsite that I could buy ultrasonic transducer?
I find 1.5mhz (or it will find 1.4 or 1.6) long bandwidth frequency transducer.
Or is it possible to make transducer with piezo crystal?

You haven't said what you want to do with this transducer, but for many applications transducers are operated at their resonant frequency to maximize efficiency. Thus you would have to use a piezo device appropriate to your operating frequency. In addition any mounting, enclosure, and interface to the transmit medium will affect the tuning of the piezo device which is very much a non-trivial design task.

That said a wide range of devices is available: Piezo Disc - STEMINC - Piezoceramic Discs, Plates, Transformers, Bimorphs and Cylinders

And there's a difference between a transducer designed for air and one designed for solids/liquids, as the
acoustic impedance is utterly different for the two regimes.